Isn't Nasri's play style similar to Mario Goetze's? If it is indeed, then I really cannot see Pep playing him. He does have a good pass and dribble in him but Pep demands high intensity pressing and possession football throughout 90 minutes. Don't know what tactics Pep is going to implement but from what I've seen so far, he like his wingers quick and dynamic, so he's not cut out for the wings either.
Not to mention, we already have two world class AM's in Merlin and De Bruyne. So I can't see Nasri being more than just a rotation player, at best.