I don't know this is a hard question. Is it no one?
Partial transformation?
if were going off any "transformation" then its killer b. So much for your answer huh.
Partial transformation?
Not really Sasuke is still more versatile when it comes to partial transformations compared to Killer Bee... Back when he had the Curse Mark he would be able use partial transformations and even when he unlocked Susanoo he was still using partial transformations his skill in that field is above others
Think of Choji for example when he uses his jutsu to make his hand/fist big instead of his whole body is considered a partial transformation
Versatile how. Killer b was uning all of the 8 tails abilities in base bar bijudama
the difference between Bee and Sasuke is that one is a Jin and the other isnt now if Sasuke was a Jin he would be able to replicate the same feats if he had Bijuu as long as Killer Bee did but the point im trying to make here is that whatever power up Sasuke recieves whether its a curse mark or Susanoo he utilises that ability to its full potential and also has a mastery of that ability to which allow him to partial transformations
if were going off any "transformation" then its killer b. So much for your answer huh.
sad trumpet plays