I just signed up to post this info. This will probably be my first and last post so I hope you 'll find this useful. If this is already known then accept my apologies.
I bought one of these a few years back and yesterday I connected my Hori Sega Saturn joystick to it, then plugged it into the PS3 to play SFIV and it worked.
The only thing is that you have to remap the buttons as it is all back to front and there isn’t a start button either, which means you’ll have to use the second controller (pressing the PS button on it, brings up the option screen) for menu control.
I haven’t yet tried it with the Sega Saturn Virtua 2 stick, playstation sticks or dreamcast sticks.
Due to the shortage/price of finding sticks, maybe this could be a temporary alternative.