If I were Pep I would try the Seria A. He has conquered Spain, Germany and now England, it would be nice to do it in Italy. Maybe he can manage Inter Milan or Juventus, but I doubt those clubs can afford him because they're not in a very good financial place right now, especially Juventus.
PSG is also another club that will fit Pep very well. I don't believe he will continue at Manchester City next season, but let's wait and see how it goes.
I am pretty sure he will fulfill his contract, which goes until 2025. I haven't heard a lot of interviews from recently, but if I am informed correctly, the issue at the moment is that he doesn't quite feel like extending his contract with Manchester City.
It's true that he has had his time in Spain with Barcelona, with Bayern in Germany and of course Manchester City in England. Whether he is a coach who would like to win titles in all the top four leagues, maybe you are right be. I wouldn't say that it is unlikely. But he would only take a job at either Inter Milan or Juventus Turin. More likely it would be Inter Milan as he remembers how close the final was in the Champions League and how well the team is set up.
But what is the chance that Inzaghi gets sacked? He would have to mess up next season. So Inzaghi's contract ends in 2025, Guardiola's contract expires in 2025, hm.... Interesting thought experiment and it might be happening.
But national teams would be after Guardiola as well and he would still have one year to prepare a team for the World Cup. He has plenty of options. But I believe this is his last season for Manchester City. It would be 9 years by then. Exactly like Klopp!