Every league has its own characteristics. And that's what makes some players who performed poorly in the previous season excel in another league. For example, Greenwood performed quite well in Ligue 1 and Antony with Real Betis, but their performances weren't as good when they joined Manchester United. On the other hand, there are some players who were stars in their previous leagues but struggled to adapt to a new one. I'm confident Hojlund can excel in Serie A, despite rumors that Inter Milan have failed in negotiations to sign him this season.
Serie A does not have high match intensity like Premier League and it is not attacking like La Liga. Italia football is renowned with its defensive art that has been lasted and tested in many decades from national team to clubs. With players, moving from a league to another new league is risky as they can fail to adapt to a new league and their career can be affected very negatively.
Moving to an entirely new league will need adaptation to the league and a new club, and a player will have to finish both adaptation well, step by step, in order to succeed at a new club in a new league. Antony can succeed in Ajax Amsterdam, failed at Manchester United, found another chapter of his career with Betis, but he can fail at another club in La Liga.