I don`t understand why overperforming your xG is a negative thing. If anything, it just shows he`s clinical.
At 21 he`s very young and has loads of time to improve, but somehow he still has 46 goals and 7 assists for club and country since the start of last season. Put him in a side with the likes of KDB, Bernardo, Foden and Mahrez and you`ll have the recipe for something very dangerous. The quality of the Fiorentina team is shocking, they finished 13th last season, and he`s still broken Ronaldo's goal-scoring record in Italy. And Serie A is not that bad. It`s certainly below the level of the PL, but there have been plenty of successful transfers from Serie A to PL in the last couple of seasons. Jorginho, Alisson, Cancelo and Salah amongst others