If Messi really decides to leave PSG, then Xavi will be able to convince him return to Barcelona, I remember how he did this with other players who are now in the team. But you are right, the team still has financial problems and this may be a reason for Messi not to return to Barcelona, although he really likes this city, his friends and family are there, and I am sure that his family also wants to return home.
This is even beyond the financial burden that the club will face. Will Messi be able to deliver as well as he has in the past if he returns to Barcelona? He's becoming older by the day, and his physical strength will steadily deteriorate, resulting in poor performance on the field.
By bringing Messi back now, I'm sure the club and the players will be reliant on him, and if he falls short of their expectations, the club will be devastated. In my opinion, he has served and contributed enough to the club; it is now time to go on and not return to his former team, not even out of pity.
You're asking if Messi can perform in Barcelona? He scored 21 goals and had 20 assist for PSG this season. This is in a team where he's not comfortable in and the team is not in good shape, but you're worried he might not perform in Barcelona?
He would do exploit at Barcelona. Messi might be getting old but he's still among the best players in the planet. There are not many players I'll pick over Leonel Messi. He may not have the energy and speed he once had but he has a lot of qualities to more than make up for that.
The only problem with Messi going to Barcelona is the financial situation Barcelona is in. Then there is also the fact that the team might rely on him again, which might halt or slow their rebuilding process. But if Barcelona can work on these two issues, then signing Messi is a big advantage to them