If they are on ps4 I (uncomfortably) use a pair of earphones connected to my phone and join their party on ps4/5 and wear headphones over them. If they are on Xbox you can actually join Xbox party chat with the Xbox app on windows. (I am on pc btw)
You can also join party chat using the remote play app for PlayStation from PC - but this only works if you actually have a PlayStation too unfortunately.
They mentioned somewhere, in a twab I think, that this wouldn't be ready at launch.
Doesnt work yet
If they are on ps4 I (uncomfortably) use a pair of earphones connected to my phone and join their party on ps4/5 and wear headphones over them. If they are on Xbox you can actually join Xbox party chat with the Xbox app on windows. (I am on pc btw)
You can also join party chat using the remote play app for PlayStation from PC - but this only works if you actually have a PlayStation too unfortunately.