I think Machida would be a nightmare stylistic matchup for him and Weidman is a more skilled, younger, more well rounded version of Chael. I can't see him beating either
Maybe he could beat Vitor if he can get him down
Yes Chael is much more personable than Weidman. But Weidman has that whole nice guy, American as apple pie thing going for him. Don't be too quick to undersell that because as much as I like Chael, he is pretty polarizing. And while that can be good for asses in seats if he is in competive fights, his fans don't want to see him get hurt and a lot of people may look at it like a gimmick or spectacle and not care. Weidman could be that champ everyone loves like Chuck.
If Chaek was younger I might feel different. Or even a little better striker. But realistically, how much left at this stage in his career does he have for the top dogs? It would be very short-lived if by some miracle it even got to that point IMO