Regarding PSG's dominance in League 1, I don't think Luis Enrique needs to worry too much even though Mbappe will leave for another team in a more different league. But Luis Enrique must also have time to think about who he will target in the next transfer window by preparing sufficient money. Because if the target is a player whose level is not much different from Mbappe, of course the costs that must be prepared are not small and I am sure that PSG has the ability to do that.
PSG still has other good players but not as good as Kylian Mbappe. If PSG loses its goal scoring machine, how can PSG compete with other clubs and dominate League 1 again? Of the total 62 goals scored by PSG this season, Mbappe has contributed the most, namely by creating 24 goals in League 1, which is almost half. If it wasn't for Mbappe, perhaps PSG wouldn't have been able to score as many goals. If PSG doesn't recruit players of the same level as Mbappe, I'm not sure whether PSG will dominate again even without Mbappe, even though PSG is known for its strongest performance in League 1, Mbappe's role in the squad is very influential.
Regarding money, PSG has good finances, so it doesn't matter if PSG has to spend a lot of money to buy the players it needs. The most important thing that Luis Enrique and the management have to think about is to think about recruiting players who have the same goal productivity as Mbappe, the one that What is most in the spotlight is Victor Oshimen, he is a striker who almost has the same performance as Mbappe and PSG also has to spend a lot of money if they want to recruit Victor Oshimen from Napoli.