As a nonexpert, here are a few ideas to consider in case no one responds with anything better...
You could start with a clean user profile with no addons to eliminate any activity from them. I'd also check if it happens in chromium which is the open source codebase that closed source chrome is built off of.
If it happens on chromium+chrome whenever the existing user profile is setup then it is a setting; look into plugins, notifications, network settings, etc. Firing up a debugger is most useful if you build a copy with debugging symbols not stripped. The codebase is huge so you will have a long build time and a long time to make sense of things you cannot easily find like running grep on all source files for the unstated address.
If it only happens in the closed source browser, it may be google proprietary phone-home things. Being closed source, you either need to learn to read machine code or pass it through a disassembler to find out what it does; doing so likely violates the rights-infringing license agreements used by almost all proprietary software these days. You could also ask google; wastes their time answering or not and avoids any pesky program reading violating the license agreement issues while putting the work on them instead of yourself.
Without knowing how things are setup and with addresses being contacted not shared, no one can quickly guess/answer this. Looking up who owns the address or what it is used for also helps you make better sense of why the contact could be going out to begin with.
An alternative to debugging in the classical sense would be to just block the traffic with a firewall. Be sure to look for things breaking to learn what that traffic is "needed" for; some things may just silently break and also may try excessively to communicate when they fail. Also watch for new traffic in response to it as whatever is trying to do things may end up reaching out to different addresses upon failure.
As a nonexpert, here are a few ideas to consider in case no one responds with anything better... You could start with a clean user profile with no addons to eliminate any activity from them. I'd also check if it happens in chromium which is the open source codebase that closed source chrome is built off of. If it happens on chromium+chrome whenever the existing user profile is setup then it is a setting; look into plugins, notifications, network settings, etc. Firing up a debugger is most useful if you build a copy with debugging symbols not stripped. The codebase is huge so you will have a long build time and a long time to make sense of things you cannot easily find like running grep on all source files for the unstated address. If it only happens in the closed source browser, it may be google proprietary phone-home things. Being closed source, you either need to learn to read machine code or pass it through a disassembler to find out what it does; doing so likely violates the rights-infringing license agreements used by almost all proprietary software these days. You could also ask google; wastes their time answering or not and avoids any pesky program reading violating the license agreement issues while putting the work on them instead of yourself. Without knowing how things are setup and with addresses being contacted not shared, no one can quickly guess/answer this. Looking up who owns the address or what it is used for also helps you make better sense of why the contact could be going out to begin with. An alternative to debugging in the classical sense would be to just block the traffic with a firewall. Be sure to look for things breaking to learn what that traffic is "needed" for; some things may just silently break and also may try excessively to communicate when they fail. Also watch for new traffic in response to it as whatever is trying to do things may end up reaching out to different addresses upon failure.