I don't think Messi will go to Arab or US leagues. He is a legend. He should leave football in a way that suits a legend. After the contract with PSG is finished, if he signed a 1 -year contract with Barcelona and leaves football, he will complete a great career. Messi does not need to go to Arab or US leagues. Messi will not be as helpless as Ronaldo. I think there will be big clubs that want to see him at least one more season in Europe.
The case is the same with Ronaldo because many of us and even me one of them don't believe that he will go to Arabia as well as with Messi's current condition. Regardless of Legend or not, all possibilities will continue to occur regardless of what current conditions money can determine.