It will vibrate badly, possibly cause issues in the bearing carrier, as well as issues with the L/U bearings. The thrust will be highly symmetrical. As a worst case, imagine what a 1-blade prop would feel like. There used to be some cheap alternatives solely for backup. I think one was called “comprop” which was cast from a composite material. Not going to like WOT with a 200+ motor, but it would get you back to the ramp back when.
