I would guess that PSG may go for a manager change as well. I know that is not talked about a lot right now and maybe that won't happen but I think that they need a bigger name. I have always said the same thing and I will keep saying the same thing until I die, what PSG needs is Zidane. They will win the league and the cup anyway, they already win the league all the time and if they cared a bit more then they would win the cup too, that is just expected at this point.
However, if they get Zidane then they may win the UCL as well, he can build a team that would be better than the current one, even without Mbappe. Dude knows his own style and he knows attacking football, if nothing else it's guaranteed that they will have fun games to watch.
But that would be the worst timing ever if they now sign Zidane when Mbappe is about to leave the club. By the way I doubt that if Mbappe leaves the club, Zidane would not want to become the coach there. They should have tried like never before when there was still Neymar, Messi and Mbappe. But I think at the time Zidane was still a coach (or again) at Real Madrid? I am not sure about the timeline back then, but I think that was the situation. Now when Mbappe leaves PSG is not the same team anymore.