I haven't really tested StarRail, but Genshin has been working flawless for months. Went from brand new account to finishing Inazuma questline and now getting into Fontaine with 0 issues(aside from one time where DXVK messed me up, but that's due to my graphics card being a ancient relic XP)
Also, tip, don't enable the FPS Unlocker. It says it makes you get detected by the anti-cheat, but I never faced this, but it seems to lag the game out? Like, with it enabled, I can't even get near Dragonspire