For N64?somebody should work on it
No one would want to do such a thing, given how the Switch already has a fully fledged emulator for N64 running very well. It'd be a waste of time for something that might have quirks, or awful compatibility.
Wii and GC would be better to dissect, given how there's no GC or Wii emulation for Switch, but as pointed out, it seems N recompiled the isos for ARM, so they work better on the Switch's hardware.