Not sure if it's easily possible. It would require installing a USB stack and then adding support to the game to read controller input from a USB device. The first part of that is easy - I have to already do that to get the debug GH2 ELF from the 80s prototype working. The second part is much harder and probably requires code modifications rather than scripting.
Edit: Just realized the chances of the post above mine being a spammer are non-zero. Oops
_________________