This is weird, you're saying the only racism is institutional racism (tho you must recall the motto Mexico is for Mexicans' as well as a history of slavery in Mexico) that attitude used to keep out legal foreigners (LatAm and NAm) from some types of jobs.
Never the less, it's ridiculous to think that a Mexican cannot be racist against an American or a Honduran or whatever.
Mexico imported slaves from Africa and that wasn't abolished till the 1830s though there was an exception that allowed importation of slaves from Texas.