There was a version of the Gravis specifically for the Amiga apparently.
http://eab.abime.net/showthread.php?t=82303&highlight=GravisFor an adaptor. Well... no. Most PC-Amiga adapters that I have seen just map the Analog style of joysticks, for proportional control. Few Amiga games support proportional analog controllers.
That isn't an analog controller, so in theory it's doable, what made a lot of manufacturers steer clear is... most all Amiga controllers had up, down, left, right, fire. No other buttons.
CD32 controllers are the exception, but very few games support multi button either. Probably more than support analog control though.
Sorry to disappoint you. I could be wrong, but it was always an issue, getting other designs of controller working on Amigas without cutting cables and soldering new connectors on the end.
I guess it's no big deal to make one, the snag is making the other buttons do useful things.
