Well, as our attack is not working like it should, it might be worth a shot. Maybe it'll give some fluidity to our attack.
That or a 442 like in Fergie days, with two strikers in him and Sanchez, two men midfield in Pogba and Fred/Matic and lingard as a right midfielder and Rashford as a left one albeit more advanced. Like Giggs used to play.
Trying Sanchez in the striker position for a game or two can't hurt. At best, we get ourself a wc attacker, at worst, the attack performs as it does right now. Clearly it's not even close to working, no fluidity, no understanding.
Plus, Sanchez has the technical ability to play in tight spaces.