imagine if the 3DS had a Wii U emulator... :O

What for? 3DS can run 3DS games just fine

I don't think this is possible!

I think he can be possible, because the Switch and the Wii U has the same performance and if you jailbreak the Switch, you can play 3DS on the Switch (not all the games are in full speed). We just need someone to make a 3DS emulator for the Wii U and that's it.