If Mexico’s President Claudia Sheinbaum said Mexico will not stop the migrants, just address them and their rights, does this mean she supports them?

She's in between the rock and the hard place. The cartels, which are immensely wealthy and powerful in Mexico, do not want their cash cow of human trafficking to dry up. However, the population of Mexico, (of the non-cartel variety), hate the migrants from South America and elsewhere cucking up their country, just as much as North Americans do.

She also doesn't want to pay high tariffs. She will walk a tightrope of political double talk, and seeming compliance with all parties concerned.