I can easily see this as an alternate costume for Pit.
...NO!
you people are just plain uncreative!
with all the weapon choices in Uprising, Dark Pit could easily have a moveset of his own that's more Semi-Clonish than pure clonish.
Up-B: Pandora's flight. twice as long as Pit's with more precise control
Side-B: Dark Pit Staff. fires a standing charge shot from his staff. can be aimed. OR: V. Maximum Overdrive Attack. the charging move he uses against Pit in the Chapter 6 boss fight.
Down-B: Gemini Orbitars. fires two Gemini Orbitar shots on either side, which then arc upwards until the meet and cancel. reflectable, can be absorbed by PSI Magnet. OR: Pittoo's Falcon Kick. basically Ganondorf's Falcon Kick rip-off except faster and a little less darkness effect.
Neutral-B: the ONLY clone move. fires his bow, exactly like Pit.
the rest of his moveset is more agressive, constisting of Kicks and Bow-strikes. DP is known for being a little kick-happy in Uprising. (He kicks Pit, he Kicks a boss and kills it, and I think there's another time he kicks, but I'm sure he does it a lot off-screen)
his down tilt is a circular kick.
See? not a clone. hardly even Semi-clonish and it fits him perfectly just based on Pit's moveset itself.
Pit's new Down-B is the Guardian Orbitars, which basically replace his Mirror Shield from Brawl, and protects him on all sides. either his Dash attack or Side B is now the Upperdash Arm, using it's powerful melee dash attack.