What? Osimhen scored 12 goals in the Belgian league, a league where Lukaku scored more at the age of 16. It's not really impressive at all. Osimhen also scored 13 goals in Ligue 1, not 16.
Scoring 10 and 14 goals in the Serie A isn't good for a striker at all. They play against the likes of Hellas Verona, Salernitana, Empoli, Cagliari etc, so while neither Osimhen nor Højlund's goal scoring was impressive at a young age, it is the combination of Højlund's abilities that make him the striker with highest potential for me.
There's more to a striker's potential than how many goals they score, you know. Højlund has 3 CL goals in 2 games, for instance, almost 4 but it was just offside. Another goal that was ruled out in the PL, as well. I'm not saying he has scored as many goals as Osimhen, obviously. I'm saying that he has more to his game than Osimhen at 20, and if he follows this progression, I think he will be a better striker than Osimhen.