

Well, you have to buy the game to try launching it without Steam. Or ask someone who did, of course. It’d be nice to know before buying.
Do note that the default shortcuts Steam uses are Steam dependent - they’re “steam://” addresses that tell Steam to load the game, not shortcuts to the game’s raw executable.
With a phone, there’s a type of controller that wraps around the phone, turning it into a Switch form factor. That’s probably the middle ground between atrocious touchscreen d-pads (or only playing games that actually work well with touch controls) versus lugging around a Dualsense and some mount contraption or kickstanding your phone on a surface.