According to several sources from Spain Mbappé just asked to PSG to be sold to REAL MADRID for this January.
Right now I wouldn't want to see him move to Madrid given that Vinicius Jr and Rodrygo have upped their game. Mbappe's arrival would mean Rodrygo would have to go back to the bench since he (Mbappe) does not want to play in the centre forward position.
Perhaps Liverpool or Manchester United may try to approach him.
Even if that happens, I'm not sure Mbappe is interested in Liverpool or Manchester United which in fact Mbappe is a very ambitious player.
I mean, Mbapee would be more interested in joining Real Madrid than choosing another club. the reason is simple, Real Madrid has a big chance for him to smooth his career and win the champions league title.
he wants to be recognized as the best player, and to realize his ambitions and dreams, the opportunity lies at a club as big as Real Madrid. however, I'm not sure SPG will release him in the transfer window later.