I do want to warn for the case of Genshin about Mihoyo banning people as the only way to get it working is with that one Anime Game Launcher that bypasses the anti-cheat.
The game still runs in SteamOS that way, and while I do know people often say it’s not often it happens or rarely gets reported of happening, it is still a risk and I remember seeing somebody having a breakdown on r/steamdeck a few months ago because they lost a ton of progress in Star Rail after doing the same thing for it on the Steam Deck.
The safest option (what I do personally) is just using it on Windows.