It won't happen. The Switch has already a 3D Mario game, and 3D Mario are heavily linked to the console they're released on.
It's no different than the 2D Mario games and one of them just got ported.
Also, Mario 64 was ported to NDS.
I'm not sure the game will ever be ported, but having a second Mario game - that has a very different feal, btw - wouldn't hurt. Leaving a new one for next gen.