I think it'll be the same as against Everton in terms of shape (kind of a 343 on the right and a 433 on the left, if that makes sense) but with Gundogan (who he likes to play in these big games) in KDB'S role and KDB in Sterling's.
Regardless of the setup I think Pep will start with 3 of Silva, KDB, Gundogan, Bernardo in order to control the game more, esp. early on. Can't be giving them an early lead.
G.Jesus was excellent at Everton and is better suited to this leg than Aguero, whether he's fit or not. Let Kun score another title winner at the weekend