I certainly understand not wanting to start over. Although according to this it should be possible to transfer the saves in case you can be bothered. I'd imagine you would get much better performance and battery life on the native version?
I love the look of the miyoo devices, I'm waiting on shipping for the Plus and am pretty excited to play with it.
I love my steam deck and have emudeck and a bunch of Roms on it, but have been spending more time getting through my backlog of more recent games on Steam than I have emulating lately. Didn't know modded BotW was possible though, what mods do you run on it?