Any of these Ligue 1 CMs potential future star potential, à la Vidal?
Jordan Veretout
Nampalys Mendy
Jordan Ferri
Corentin Tolisso
Tiemoué Bakayoko
Abdoulaye Doucouré
N'Golo Kanté
Gueïda Fofana
@Fred @Cheesio @Osman @frenchies
That is such a random list of players

A lot of the names you mentioned are average players IMO, at least from the perspective of a club like Juventus.
Anyway, there are very different players in that list. Some of them are strictly creative type players, such as Veretout, he is predominantly a trequartista, but plays well as a CM. Very good passer of the ball, decent creativity, though I wouldn't expect him to be good enough to play for a top team tbh.
Then you have average players in there like Doucoure and Mendy. I'm actually surprised you even heard of such players
N'golo Kante is a player that's talked about a lot, I haven't seen enough of him to be honest, but the few times I have seen him this season, he was ok, never really stuck out though. Seemed to me like a very strong player for his size, and was a strong defensive player.
I've seen a lot of the Lyon trio: Fofana has been out injured for the vast majority of this season, so he didn't really play this season, which was a shame, because he looked like a decent prospect the season before last, and would have helped Lyon this season. He's a good all round midfielder he's a box to box mid; bags of stamina, he works very hard, he's a good tackler, he's comfortable on the ball, but not really much of a passer. I don't know if he'll ever make it though, because of his injury problems at such a young age.
Ferri is a decent player, neat passing kind of player that is nice to have on the team, but really isn't that special at anything. He's also not that young to be honest.
Tolliso had a very good season, I hadn't seen him play before this season, so my judgment on him is strictly from what I've seen this season. Very strong player, also a box to box midfielder, but he's got a very strong shot on him, and actually scores quite a few goals. I think he's probably the best midfield prospect in Lyon right now.
Bakayako is someone I've seen a bit of too. He looks like a real good prospect, Monaco bought him from Rennes last summer where he had a good season. Unfortunately he didn't get much playing time in Monaco, but whenever he played, he did very well. He's not a box to box player like Tolliso, he's more of a sitting defensive midfielder, and a really good one at that. Very strong defensively, he's also got good physique and is very good in the air. I'm expecting him to get a lot more game time next season now that Kondogbia is gone.