Bellingham holds great promise but he's not kicked a ball in the EPL.
All these so-called dead certs in the BL; how comes BVB didn't smash the Europa League this season?
He doesn't need to. He was starting for Birmingham in the championship at 16 and was the best player on the pitch almost every time he played. He's now been ripping it up in the BL at 18 (!!!) and whenever he plays for England he looks a class above his compatriots.
Also Frankfurt won the EL. Cup competitions aren't always the best indicator, Leipzig & Dortmund probably didn't focus it as much as clubs like Rangers or Frankfurt did. Bellingham is about as close to a sure thing as you can get, he's worth 10 of a Hojbjerg or a Bentancur.