Osimhen will be a good striker for PSG due to their style of play and the gravity of the League. If he joins PSG, he will record a lot of goals in the League one since he have scoring abilities and he get good players that will serve the ball and create chances for him.
In my opinion, I will want Osimhen to join either a Premier League team or a Laliga team in order to show his greatness because people are still doubting his abilities as world class striker.
On the other hand, I don’t think Osimhen will not leave Napoli at the end of the season because he is keen to more challenges in his career, and he will like to play for his dream teams.
If Osimhen is able to maintain good team communication and always gets support from defenders who often provide good passes, then there is an opportunity for Osimhen to score lots of goals, but if Osimhen cannot maintain a good relationship with his team, then he will not be able to score as many goals as he did. As you said, this shows that there is no guarantee that Osimhen will play well at PSG.