I am also very sure that if Mbappe goes to La Liga, he will stay at Real Madrid, not Barcelona. I once read the news about his dream club that he wants to play for is Real Madrid, not Barcelona at all. Mbappe is an extraordinary player, and he has been so often rumored to be going to Real Madrid according to expectations. However, it is PSG who still object to this. So, this seems like a very small possibility if Mbappe suddenly turns to Barcelona.
On the other hand, maybe the match that will be exciting is Nice vs Marseille. Nice has proven that its performance progress so far is beyond expectations, and is runner-up in the French League. His consistency is quite good in every match. On the other hand, sometimes Marseille also puts quite strong pressure on the opposing players. So, it gets a little more interesting later on. Yes, even though the French League is not like other leagues where the competition is very tough, at least for now, PSG's dominance is not as strong and strong as before.
I don't think Mbappé would move to Barcelona, he's been linked with Realmadrid in the past and even had a secret negotiation with them this summer so if he's to move to any club in the Laliga it would definitely be Realmadrid and not Barca, Barcelona are not very strong financially to afford Mbappé talk more of paying his wages if they manage to sign him, they're currently owing and have got some players to take a pay cut to remain at the club, therefore I don't think it would be possible for Mbappé to move over there.
Nice have been very impressive this season unlike the previous one, I'm really impressed with their performance cause they've made a really good progress this season, they're the only team in the Ligue one that are yet to be unbeaten and are in the 2nd place with just a point separating them from Monaco that's in 1st position, well I think Nice are more favourites to win against Marseille cause their performance is better and they'll be playing with a home advantage.