Now the real question is.

Can I emulate WiiU games on my Desktop PC while using the Steamdeck as the pad/2nd screen?

MC3 works great in PCSX2 on Deck.

There’s also Midnight Club L.A. Remix for the PSP which I recently 100%'d through PPSSPP. It’s closer gameplay wise to MC3 than the full console version of Los Angeles.

Sadly Midnight Club Los Angeles still kinda sucks to emulate at the moment. but someone is working on a re-compilation of the game for PC. But seems like that going to take a while even if things go well…