Mega Drive had the six-button controller beat at the time... despite being made later. Still a legitimate controller though.
https://www.youtube.com/watch?v=x9Vw7zX4OX0
It's more of the port than the controller though.
Also it's not being made later, it's developed before SNES Turbo but published after SNES Turbo.
The story's kinda complicated.
The first port of Street Fighter II CE for Genesis first was handled by another company which Capcom didn't like the result so they make the port itself (Street Fighter II Special CE) but making it from scratch again with the deadline's already approaching was hard.
Not to mention it's the first time Capcom ever made a game for SEGA Mega Drive.
The complete history could be read here :
Link :
https://hiddenpalace.org/News/The_Lost_Street_Fighter_II:_Champion_Edition_for_Sega_Mega_DriveIt's a very long but enjoyable read.
Other Capcom games on Mega Drive before Street Fighter SCE wasn't even made by Capcom themself.
For example Ghouls'n Ghosts, Forgotten World, and Strider was made by Sega R&D 2, not Capcom.
Thankfully the controller was adapted into Saturn controller and almost all Capcom port on Saturn were good which is making all Capcom games are all heaven to arcade fighters.
Especially since the layout buttons layout are same with Capcom arcade's version, moving between arcade and Saturn was a cakewalk.