Steam sometimes lets you know with a banner in the store page about a required 3rd party software, but there's also https://areweanticheatyet.com/ maintained by Linux gamers.

What's frustrating to me is that games will run the hyper invasive kernel level version of an anti cheat on Windows but will allow Linux plays, which has no such level of access. If we're trusting Linux players with no kernel level monitoring, why not windows players? Have cheater really not caught on that there's a lower bar on that platform? I hope they don't because I like being able to play competitive games with friends without having to reboot first.