Bought one of these....
It's some PS3/PC joystick called "RockSoul" and there's virtually no trace of it on the internet. But some guy on ebay is selling them CIB for $25 shipped.
On the inside, it looks suspiciously like a stripped down Qanba Drone.
Anyway, snipped everything out of the joystick. (who the hell needs a direct input controller?) Left pigtail wires in case I wanted to restore it back. Select and Run are wired to those two little buttons at the top right. I - VI are in a SF2 layout. The rightmost buttons will eventually be made into redundant Run/Select buttons for those "three button" PCE games. I've got 16MM toggle buttons coming in the mail to fill those five holes. That will cover mode, slow motion, and turbo I and turbo II
So everything is working great for SF2, but I'm having some weird, weird issues with the PCB. Basically when I plug it in, it's throwing a Select input at the console. And seems to do so randomly. If I boot it up into CD mode, it goes to the memory management screen and I can't get out of it. I can't control my Everdrive clone menu with it. But I can hit select to start the most recently loaded game. When I play Strip Fighter 2, I can control the menus and character select screens perfectly. In an actual fight, my character does nothing. But I can pause!
Not entirely sure what's going on. Perhaps a ceramic capacitor between select and ground?