I used Standard-Settings in Steam. I have to set "/gldevice:Vulkan" as Start-Parameter, otherwise it's unreliable if the Game starts. If the Game starts without this Parameter, then it mostly runs fine, except for Chapter 5 (Mirror-Temple) where a graphical Glitch occured. I didn't test the Steam-Overlay without that Parameter tho.

For some unknown reason, the Game won't start the Native Linux-Version for me anymore. But in Proton and with the given Start-Parameter, everything runs.