It doesn't matter who you sign, you're never going to play like City while Mourinho is manager. He's always built his sides on a strong defence and then pace, power & physicality in attack. You could have put Coutinho in your midfield (along with Pogba) and City would have still dominated possession - every player Guardiola picks has to be comfortable on the ball, able and willing to play the ball in tight areas. Guardiola sacrifices the pace, power and physicality Utd have for players that are capable of dominating possession and Mourinho the opposite, he'll take a Fellaini or Matic over a 5'5 technical midfielder every day of the week. This is the reason whenever people do these combined 11's they're all a crock of ****. No matter how good people think Pogba is, he's never getting in Pep's midfield and equally Silva isn't getting in Mourinho's midfield*.
I've said it 100 times before, Utd never wanted Mourinho as their manager. We know they tried to get Pep and Klopp but missed out and even settled on Moyes over him - his antics and style of football is why. They've only gone for him because of the disastrous jobs Moyes and LvG done - he was the safest bet to establish them back in the CL and protect the value of the club. Every time Mourinho gets a new job we're told he's changed but every time he's the exact same Mourinho as before.
*He might stick him out on the wing if he didn't have anybody else but he's never playing him in an orthodox central midfield anyway.