Funny little bug with Aegislash using Power Trick

My Aegislash used Power Trick and then I had it swap forms to use iron head for some bonus Dmg and my game immediately crashed. Is this just not allowed and the game crash is a failsafe? or did my game actually choke on its spaghetti due to an internal issue?

tried to do it myself, didn’t crash for me. probably a game issue instead of a bug