I have read about these rumours but it looks like PSG can't let Mbappe go because he is one of the main players in the attacking position for the PSG team.
If Mbappe really leaves PSG then it will be difficult for PSG to find a replacement for Mbappe.
Maybe later there will be more negotiations being carried out by PSG management to Mbappe so he can stay there a little longer.

But if this really happens so that Mbappe is taken by Real Madrid then this is a golden opportunity for Madrid to be able to have a good attack line for the summer.