https://github.com/retropie/retropie-setup/wiki/Super-Nintendo-Entertainment-Systemthere are a few file extensions for SNES Roms that are accepted by most emulators as you likely know, seen in this list. Whether all or some of these will be accepted on SNES mini is anyone's guess. You'll have to give the experts a week at least before we know how to hack the SNES. if you remember, it took a few months before we had that simple hacking program for the NES classic.
have patience