Luke Skywalker is the original protagonist of the Star Wars saga.
In "Phineas and Ferb: Star Wars", he lives one moisture farm away from Phineas and Ferb. They had visited him and asked him if he wanted to trice out his farm like there but Luke said no because Uncle Owen likes doing it the old fashion way. He made a bunch of cameo's at the death star he was wearing a Storm trooper suit in the garbage shoot and leaving the death star. He was last in the end of the Rebel song.
As same physical appearance in all Star Wars Trilogy.