The best thing IMO is to arrange an agreement with Man U involving player swaps. We don't need to play with a full regista. But I can't help but worry that if we swap Pogba for Pjanic, we will be missing a playmaking presence.
So perhaps something where we can swap a few players - to Mourinho's liking.
Maybe we can arrange something between Pogba+Herrera for Khedira & Pjanic
Herrera is a complete player and can pass. Both Herrera & Khedira have 1 year left. Pogba & Herrera are perfect for a 4-3-3, while Pjanic & Khedira are great in a 4-2-3-1.
Perhaps we need to give a bit of $. But it should be minimal. Both coaches probably end up happy.
Midfield of:
Pogba-Can-Herrera