I don't think Pogba will ever be the player for United that you need him to be.
Look at the midfielders he was playing or competing with during his seasons at Juve.....
12/13 - Pirlo, Vidal, Marchisio
13/14 - Pirlo, Vidal, Marchisio
14/15 - Marchisio, Vidal
15/16 - Marchisio, Khedira
He played with some of the best midfielders in the world at that time, which allowed him a lot more freedom and allowed him to get away with things he is now being found out for.
He's come in at United and has been playing in a midfield with the likes of Herrera, Fellaini, occasionally Blind, an ageing Carrick, McTominay and Matic. All very good players on their day, but a step down from the consistency and quality he played with at Juve. The onus is now on him to be the main-man and to bring the quality up of those around him. He doesn't seem capable of being able to do that.
The point is highlighted by the World Cup, when he found himself in a midfield with Kante and Matuidi, and low and behold he's a world-beater again!
What's more, Juve haven't really missed him. If anything, they're a better team since he left.
You either need to make massive improvements to the midfield and team around him, or move him on.