A new filing made by Nintendo with the FCC has appeared in their database, showing off the backside of what seems to be an SNES controller. The filing’s name indicates that the controller is wireless. [Thanks, Resetera!]
While not proof that these will be announced in the near future, nor that SNES games are coming to the Switch, it should be remembered that the Switch currently has wireless NES controllers that are meant to be used with the Nintendo Switch Online NES games. It wouldn’t be unlikely that something similar could be released if SNES games did join the online service.
It should also be noted that back in January, some text strings for SNES games on the service, including some game descriptions, were also datamined.