Valve has an input translation layer called Steam Input, originally mostly used with the Steam Controller, now well integrated with the Steam Deck. Keys can translate to buttons, mouse movements to analog sticks/touchpads, etc. Users can contribute Steam Input configs for a game that other users can try, download, and rate. I’ve used a community layout at length on the Steam Deck (for Subnautica) and was satisfied, though it’s a bit confusing when the game says “press T to do such‐and‐such” and I have to try all the Steam Deck buttons until I figure out what T got mapped to.