Do love how people say Rashford is not a striker when he idolised fat ronaldo when he was a boy and I'm pretty sure he stated during the Mourinho years he wanted to play through the middle.
To be an inverse winger, you need to be strong in all forward aspects. Rashford is not. He isnt very good at crossing a ball and he isnt particularly clinical. So besides being a pace merchant who you can long ball it (air or ground) behind a defence, what does he excel at?
Robben at his age, was light years above Rashford. He isnt very tricky like a Ribery or Hazard. He wont come close to C.Ron.
Comparisons with Anelka are way of the mark. He was never played on the wing. He played in the space between a 10 and a 7, deep lying forward. Carlo played a Xmas tree after he failed to implement a diamond formation and Anelka ghosted between the lines.
You can hope that rashford grows into a true role but to define someone as 'forward' shows pretty much that no one can define his strengths or where best to play him. A phil jones, jack of all trades player.
In fact he is holding you back, you dont have a real winger besides James in your squad. So he will have to take up a centre forward place in your side, ironically where you say he cant play.