Pogba can play in a pivot, but with a #6, someone like Kante. I think Matic/McTominay can do the role well. I think he struggled with Utd in the role because not only did he have to bring the ball out, but also be the creator, because Pereira/Lingard were crap at creating from the #10 position. I think now with Bruno shouldering that responsibility, Pogba can play his games as the deep lying playmaker/the link player between the defence and attack.
Pogba--Matic
------Bruno
In this setup, VDB can play Bruno or Pogba's role. But with Fred also playing Pogba's role, I'm assuming we would be getting VDB to replace Andreas/Lingard. Thats fine. But it would be very underwhelming if we replace Pogba with VDB.