Quote Originally Posted by blue phoenix
does it require a complex materia setup? the japanese version seemed to be full of materia (it all looked command though)
The materia in that video is simply Mime=Counter x8, although in the battle a HP Plus, MP Plus and two other materia are replacing two set as Barret's HP and MP are maxed and he only counters six times.

A character can Mime their own Limit Break as long as nothing happened between them performing their LB and them selecting Mime.