Similarly to Brazil, Liga MX also doesn't have set rules for championship stars on clubs crests, however, it's not as random as the Brasileirão.
Clubs like Cruz Azul, Santos Laguna, Leon, Xolos, Necaxa, and others, have a star for every league title they've won.
Pachuca has it's stars separated in two section. The blue stars above the crest are the national Mexican titles it won, while the gold stars underneath are international titles. Interestingly, 4 of those are CONCACAF titles but 1 is the CONMEBOL Copa Sudamericana, a South American tournament were Mexican clubs were periodically invited. To this day Pachuca is the only club from a different continent to have won in South America.
Monterrey also follows the same structure, national titles above and international below. Rayados, however, only celebrate top-tier trophies despite having won championships both nationally and internationally of less importance.
Other important teams prefer not to have any stars on their crest and maintain a cleaner look. Club America, for example, has never had them, but Chivas, Pumas and Tigres have in the past but decided to remove them.
