I thought this myself, especially towards the end of the last game when Cavani came on. Rashford went right side and had discipline to stay there, and actually gave us an outlet that side rather than always looking left for a pass.
The skillset isnt too much different from him playing left side, he can still look to shift the ball to his right foot and get a shot off, only difference would be he moves to the outside of the full back before shooting rather than into the congested centre. And a shot from the right towards the far post has a good chance to be parried into the path of one of the players coming from the left.
We are so one dimensional moving the ball to the left that defending us becomes an easy task. The opposition left back can tuck in and defend the width of the penalty box, that anyone cutting in from the left is having to go through a wall of defenders anyway. So I feel like while maybe he wouldnt get as many chances total, the chances he would get would be clearer and lead to more second chances for the rest of the team, and just generally more space for the likes of Bruno/Pogba to operate in.
I think of the role Pedro used to play for Barca as a perfect example. He wasnt a winger, he was a right footed inside forward who played on the right as well, but had the discipline to stay wide when needed and only come inside when the moment was right.
And ultimately if we have anyone on the team who would have the right attitude to play a role they dont like for the benefit of the greater good, Rashford would be the one I'd pick.