I'm now releasing the first version of this mod. It's still not perfect but I didn't want to keep you guys waiting for too long (oh wait, i already have...):
Get the plugin here:
And the converted xbox peds here (with flipped frame hierarchies, for better compatibility):
See the README for installation instructions and a list of known bugs (there are bugs!).
Huge thanks to Fire_Head for fixing a few things and most importantly implementing the cutscene hands.
Original post from before it was released: