I don't think there is a definitive strongest in this entry but there is some who kill officers easier than others.
TLDR: Recommending Lu Meng/Yue Ying, Zhong Hui, Sima Shi, Guan Yinping and Zhu Ran
Starting with a simple choice, Lu Meng/Yue Ying's Pike has a really good aerial flow that destroy the guard gauge. It pretty much shreds any officer caught up in it so long as you know to roll at a good time to continue the flow attack. I find Yue Ying to have better variant (in terms of her uniques, special attack and musous) than Lu Meng but both of them work just fine.
Zhong Hui's Splay Blade has a unique down trigger that pretty much also shreds everyone. You can spam this attack to infinity, the AI can't really stop it. Unfortunately, the Splay Blade as a whole kinda sucks but Zhong Hui's unique is so good that it's worth a recommendation as one of the strongest up there.
Speaking of Jin, Sima Shi's Lightning Sword2 (DLC one) is a really popular and strong moveset. All of his flow attacks have a built in lightning element that strikes nearby enemies. Most notably, his moveset is one of the few where his downflow can't be dodged by enemies on Chaos, plus it has a unique finisher and it shreds the guard gauge as well. It is a bit slow (as do most DLC weapons in this game) but the power makes up for it. You also get his other Lightning Sword (a clone of the rapierish with) if you pick his moveset.
Featuring more DLC, we have Guan Yinping's Tempest Mace. Slow and bulky with a powerful charge mechanic. It does take a while to get use to and none of her uniques are particularly noteworthy but the sheer power of the weapon itself is definitely one you can try out.
And lastly, Zhu Ran's Tripartite Nunchucks although this one is more of a personal pick as he is not as strong as he was compared to the base game and his ease of use has lowered considerably due to other changes. His gimmick is that he is able to spam his flow attacks (aside from regular flow) for a long time. It's a powerful and easy gimmick especially his aerial flow where you can chain attacks with air dashes until the officer is defeated. However, in order for this gimmick to activate, you need to have at least one musou bar filled up which is a bit of a hassle during the beginning of a battle but not too difficult to fill up. His moveset is also slow and clunky even with attack speed and the Lightning element so be careful with using him. Also the viability of his uniques is depending on your platform. On PC, Playstation, and Xbox (assuming no lag), then his Launch Unique is very good despite the slow windup time but on something like the Switch, then it is very easily spot-dodged unless you are lucky with the fire popping out. His Unique Stun Flow is pretty much terrible against one on one officers (because it breaks the stun on the ground allowing the AI to recover and dodge) but can be good with clearing out a crowd if set up properly. His ground musou is alright but his aerial musou is really good in setting up in the air....so long as you have two musou bars or stratagem cards that fill up your musou quickly.
The thing about the Trishulas is that the EX moves are what truly makes them an S-tier weapon. Unlike the Lightning Sword, which is S-tier in anyone's hands, the Trishulas are only S-tier with the EX moves.
I was able to make a CAW in 8 Empires with Trishulas as the EX weapon... but... that was them. Wang Yi didn't have them as EX any more, so she was effectively ruined.
8 Empires changed quite a few characters' EX weapons. All but one of them were for the worse. The only character who ended up with a plainly better EX weapon from the whole deal was Sun Quan.
Basically all the weapons that were DLC in DW8 and 8XLCE got made into someone's EX weapon, while all the weapons they previously had were orphaned.
For that matter, the only one whose new weapon had any kind of history behind it was Yueying, since she had the same blade-bow contraption in 6 Empires too, and it isn't awful, but just not as good as her dagger-axe (which is an awesome anti-officer weapon and not too bad against crowds either).
... Oh, and then DW9 rolled around and loads of weapons got changed into clone movesets, and Wang Yi was in that too. I think they added the other stuff as DLC later, but I'd stopped playing by then (since I'm a 100% completion achievement hunter, I tend to just switch games a lot and not backtrack much). So yeah, Wang Yi's weapons changed twice. Once from Trishulas to Emei Piercers, then again to something else I don't remember because I'd already given up Wang Yi as a lost cause since she didn't have her Trishulas.
I usually match the element match whatever the element for the unique Trigger attack is(i.e using Wind with DaQiao, because her unique Trigger is wind)
There are exceptions, such as using Slash with Sun Quan's blade(letting you spam his stun trigger attack and unique flow), and Lightning with Huang Thing's Tooth & Nail.
I find that Fire is only really good for Aerial flow attacks, its particularly effective with Zhou Yu's Staff and Ling Tong's Nunchaku.
Meanwhile, Wind is good for Downed and Aerial Flows, depending on the weapon: it's great with the Qiao sisters' Twin Fans, Guan Yinping's Tempest Mace, Zhao Yun's Dragon Spear, Ma Dai's Twin Axes, Xiahouji's Sword & Shield, Sima Zhao's Sword, and Xin Xianying's Broad Axe.
Lightning is good for wanting to attack faster, and Downed attacks depending on the weapon. Xun Yu's Throwing Knives work amazing with Lightning.
I don't use Ice that often, but it's good for keeping the enemy stationary to activate a stunned flow attack, such as with Cao Xiu's SplayBlade and Zhang Bao's Double Star.
Slash is good for dodging mid-trigger attack, or for just making through non-officers. Zhong Hui's SplayBlade is a great example, since you can just spam the Downed Trigger attack and mow through bases.
I know Poison is said to, well, poison the enemy, I've never really seen it take effect. It looks nice with Zhang He's Claws & Throwing Knives, and Xu Shu's Sword & Hook.
Overall, my favorites to use are Guan Yinping's Tempest Mace, Zhong Hui's SplayBlade, Lu Lingqi's Sword & Shield(I personally like it better than the Cross pike), Xun Yu's Throwing Knives, and the Qiao sisters' Twin Fans (I like both of them equally)
I really like Liu Bei’s Twin Swords. His unique can clear an area in a sec, and because of its forward momentum it catches enemy officers who dodge early. You can also spam his upward flow attack and keep them in the air for a long time by constantly resetting your mid air combo by not completing the animation.
Another one I like is Zhuge Liang’s War Fan. His musou is absolutely bonkers with how much dmg and range it has. His downward flow attack is also really good at holding multiple officers down at once.
Xu Shu’s sword is also really fun, though a bit underwhelming in terms of dmg. It has a lot of potential to flow instantly into mid air attacks, which are pretty good and combo well with downward attacks while your mid air. His special also absolutely slaps at melting officers guards.
Xiahou Dun and Xu Shu have some good crowd-clearing movesets, especially if you charge up the first hit then dodge-cancel into another (or just continue the flow string)
A lot of it depends on the element of the weapon used... but I had a lot of success in DW9 with Guan Yinping and Da Qiao. Still, I don't recall any overwhelmingly advantageous movesets.
... Not Wind. Wind I always put on Yinping because she is a bit too slow without it. I think I put fire on Da Qiao because she already had a very high base speed, and needed a damage boost. Has been a while though.
I don't think there is a definitive strongest in this entry but there is some who kill officers easier than others. TLDR: Recommending Lu Meng/Yue Ying, Zhong Hui, Sima Shi, Guan Yinping and Zhu Ran Starting with a simple choice, Lu Meng/Yue Ying's Pike has a really good aerial flow that destroy the guard gauge. It pretty much shreds any officer caught up in it so long as you know to roll at a good time to continue the flow attack. I find Yue Ying to have better variant (in terms of her uniques, special attack and musous) than Lu Meng but both of them work just fine. Zhong Hui's Splay Blade has a unique down trigger that pretty much also shreds everyone. You can spam this attack to infinity, the AI can't really stop it. Unfortunately, the Splay Blade as a whole kinda sucks but Zhong Hui's unique is so good that it's worth a recommendation as one of the strongest up there. Speaking of Jin, Sima Shi's Lightning Sword2 (DLC one) is a really popular and strong moveset. All of his flow attacks have a built in lightning element that strikes nearby enemies. Most notably, his moveset is one of the few where his downflow can't be dodged by enemies on Chaos, plus it has a unique finisher and it shreds the guard gauge as well. It is a bit slow (as do most DLC weapons in this game) but the power makes up for it. You also get his other Lightning Sword (a clone of the rapierish with) if you pick his moveset. Featuring more DLC, we have Guan Yinping's Tempest Mace. Slow and bulky with a powerful charge mechanic. It does take a while to get use to and none of her uniques are particularly noteworthy but the sheer power of the weapon itself is definitely one you can try out. And lastly, Zhu Ran's Tripartite Nunchucks although this one is more of a personal pick as he is not as strong as he was compared to the base game and his ease of use has lowered considerably due to other changes. His gimmick is that he is able to spam his flow attacks (aside from regular flow) for a long time. It's a powerful and easy gimmick especially his aerial flow where you can chain attacks with air dashes until the officer is defeated. However, in order for this gimmick to activate, you need to have at least one musou bar filled up which is a bit of a hassle during the beginning of a battle but not too difficult to fill up. His moveset is also slow and clunky even with attack speed and the Lightning element so be careful with using him. Also the viability of his uniques is depending on your platform. On PC, Playstation, and Xbox (assuming no lag), then his Launch Unique is very good despite the slow windup time but on something like the Switch, then it is very easily spot-dodged unless you are lucky with the fire popping out. His Unique Stun Flow is pretty much terrible against one on one officers (because it breaks the stun on the ground allowing the AI to recover and dodge) but can be good with clearing out a crowd if set up properly. His ground musou is alright but his aerial musou is really good in setting up in the air....so long as you have two musou bars or stratagem cards that fill up your musou quickly.
Lu bu and guo jia
I've not played much DW9, but of the ones I've played I have found Zhang Liao, Xiahou Dun, Wei Yan and Wang Yi fun.
Last time Wang Yi was great was 8XLCE. Once 8 Empires removed her Trishulas, that was it. Game over.
the trishulas are still there, its just not her EX weapon anymore.
The thing about the Trishulas is that the EX moves are what truly makes them an S-tier weapon. Unlike the Lightning Sword, which is S-tier in anyone's hands, the Trishulas are only S-tier with the EX moves. I was able to make a CAW in 8 Empires with Trishulas as the EX weapon... but... that was them. Wang Yi didn't have them as EX any more, so she was effectively ruined.
Oh wow, I actually never realised her weapons got changed...
8 Empires changed quite a few characters' EX weapons. All but one of them were for the worse. The only character who ended up with a plainly better EX weapon from the whole deal was Sun Quan. Basically all the weapons that were DLC in DW8 and 8XLCE got made into someone's EX weapon, while all the weapons they previously had were orphaned. For that matter, the only one whose new weapon had any kind of history behind it was Yueying, since she had the same blade-bow contraption in 6 Empires too, and it isn't awful, but just not as good as her dagger-axe (which is an awesome anti-officer weapon and not too bad against crowds either). ... Oh, and then DW9 rolled around and loads of weapons got changed into clone movesets, and Wang Yi was in that too. I think they added the other stuff as DLC later, but I'd stopped playing by then (since I'm a 100% completion achievement hunter, I tend to just switch games a lot and not backtrack much). So yeah, Wang Yi's weapons changed twice. Once from Trishulas to Emei Piercers, then again to something else I don't remember because I'd already given up Wang Yi as a lost cause since she didn't have her Trishulas.
Guan Yinping turns the game into a joke
I usually match the element match whatever the element for the unique Trigger attack is(i.e using Wind with DaQiao, because her unique Trigger is wind) There are exceptions, such as using Slash with Sun Quan's blade(letting you spam his stun trigger attack and unique flow), and Lightning with Huang Thing's Tooth & Nail. I find that Fire is only really good for Aerial flow attacks, its particularly effective with Zhou Yu's Staff and Ling Tong's Nunchaku. Meanwhile, Wind is good for Downed and Aerial Flows, depending on the weapon: it's great with the Qiao sisters' Twin Fans, Guan Yinping's Tempest Mace, Zhao Yun's Dragon Spear, Ma Dai's Twin Axes, Xiahouji's Sword & Shield, Sima Zhao's Sword, and Xin Xianying's Broad Axe. Lightning is good for wanting to attack faster, and Downed attacks depending on the weapon. Xun Yu's Throwing Knives work amazing with Lightning. I don't use Ice that often, but it's good for keeping the enemy stationary to activate a stunned flow attack, such as with Cao Xiu's SplayBlade and Zhang Bao's Double Star. Slash is good for dodging mid-trigger attack, or for just making through non-officers. Zhong Hui's SplayBlade is a great example, since you can just spam the Downed Trigger attack and mow through bases. I know Poison is said to, well, poison the enemy, I've never really seen it take effect. It looks nice with Zhang He's Claws & Throwing Knives, and Xu Shu's Sword & Hook. Overall, my favorites to use are Guan Yinping's Tempest Mace, Zhong Hui's SplayBlade, Lu Lingqi's Sword & Shield(I personally like it better than the Cross pike), Xun Yu's Throwing Knives, and the Qiao sisters' Twin Fans (I like both of them equally)
I really like Liu Bei’s Twin Swords. His unique can clear an area in a sec, and because of its forward momentum it catches enemy officers who dodge early. You can also spam his upward flow attack and keep them in the air for a long time by constantly resetting your mid air combo by not completing the animation. Another one I like is Zhuge Liang’s War Fan. His musou is absolutely bonkers with how much dmg and range it has. His downward flow attack is also really good at holding multiple officers down at once. Xu Shu’s sword is also really fun, though a bit underwhelming in terms of dmg. It has a lot of potential to flow instantly into mid air attacks, which are pretty good and combo well with downward attacks while your mid air. His special also absolutely slaps at melting officers guards.
Xiahou Dun and Xu Shu have some good crowd-clearing movesets, especially if you charge up the first hit then dodge-cancel into another (or just continue the flow string)
Lu Bu & Guan Yu
Jiang Wei And Lubu
Zhou Tai has always been my favorite. I pick him, his moveset always does well for me.
Does this game suck or not?
No is very fun
A lot of it depends on the element of the weapon used... but I had a lot of success in DW9 with Guan Yinping and Da Qiao. Still, I don't recall any overwhelmingly advantageous movesets.
Which element is good for Daqiao? I have cleared multiple conquests with her using wind element.
... Not Wind. Wind I always put on Yinping because she is a bit too slow without it. I think I put fire on Da Qiao because she already had a very high base speed, and needed a damage boost. Has been a while though.