Is high speed buffet possible at supersonic speed? Since high speed buffet is caused by boundary layer separation due to shock wave and at supersonic flight there is no shock wave directly onto the airfoil (it is attached to the trailing edge), is high speed buffet then possible?
All pilots who transited into supersonic speed on older designs which were not perfected for transsonic flight reported that suddenly all that shaking and vibrating stopped and flight became smooth again as soon as they went over Mach 1.

So the answer is no. With supersonic speed the buffeting stops.