Well right now he is playing 2 holding mids as mezzalas, in Sturaro and Khedira. All you have to do is invert the CMs positioning with Pjanic and it looks reasonable.
Pjanic
Marchisio-Rincon
You can play this in a 3-4-1-2 or in a 4-2-3-1. If you want Dybala to stay at SS then you play 3-4-1-2. If you want him wider so you can include Pjaca/Cuadrado then you play 4-2-3-1.
But I don't see how Sturaro and Khedira as box to box is a solution. It's far from the solution in fact.