I’d say it depends on stringent you want to be on the “activated with hand signs” flavor. I’d say you couldn’t use wushu that activated with Legerdemain and possibly not Crafts, but the others are probably ok thematically. Or you could say that they can’t use any until their hands are freed and make Grappling a way to incapacitate characters that are strong in wushu.
How would you guys run this?
-Oni