I think his arrival alligns everything for a 352. With Chiesa gone, that way we would maximize our best players, in positions that suit better for them: Vlahovic (strong CF), Dybala (SS), Cuadrado (RWB), Locatelli (CM or regista).
McKennie would be perfect as the box-to-box CM (il nuovo Vidal), De Sciglio has done pretty well before as a LWB for Italy, Bonucci and Chiellini speak for themselves.
Have Danilo and Sandro as backup RCB and RLB if needed, since we only have 04 CBs.
This would also suit the absolute lack of winger play in this team (Cuadrado is the only one who can do it).
Fill the 3rd midfield spot with whoever is available/in best form.
Sczez / Danilo - Bonucci - Chiellini / Cuadrado - De Sciglio / Locatelli - Anyone - McKennie / Dybala - Vlahovic
Sounds good, no?