Yeah, the HP code is interesting. It seems to be an issue when you are facing someone with more than one pokemon, At least for me, their fist pokemon goes down, but when they bring out the next one it also has unlimited HP and simply disabling the code does not fix it.
The switch emulators on pc rely on your CPU mostly, and they only use a single core, so GPU not as important as a good CPU. I don't use switch emulator, but many here do, and willing to help.