Mexican players who have been in Europe and played decent minutes and then come back to MEX usually do drop in form after a few months. Examples Galindo Maza Pardo Salcido
Osorio won a title I think. Marquez has been retired since he joined the MMLS. I think some of these guys are in a different boat, if they come back after the cusp of their careers (Maza, Osorio, Marquez, Pardo...) then that's not too bad or strange... But Juarez, Barrera and others, too bad they may not flourish during their golden years (~26-29). /p
Barrera actually hasn't been that BAD whenever I watch Cruz Azul games when I need to catch some zzz's