The "What Games/Platforms Could Come to NSO" Thread

[Leynos]

PC Engine

SEGA Saturn

SEGA Dreamcast

SEGA Master System

SEGA Game Gear. 

Neo Geo 

All of that is pretty easy to emulate these days. Saturn used to be difficult, but not anymore. Switch 1 is running Saturn emulators with the ports on it from City Connection. They are running on a Saturn emulator.