I have the steam deck. Got it when it came out.
I haven't hard modded it, but I do have a ton of emulation of it, for old school systems, plus the nintendo switch.
It plays a lot of switch games pretty well, but not all. Some freeze, some lag, but most I've tried play well enough.
I haven't tried getting PC game trainers to run on it yet or cracked games, but they are guides that say it can work.