They're calling the Phillipines the South East Asian Mexico. I'm assuming they also mean Mexico is the equivalent of a SEA country for Central America.
It's a good way of removing the features of something that are disgusting and replacing them with something likeable. A cute anime girl can't be intimidating, and it's hard to dislike her. Replace an invading coloniser that SA's the local population with her and it becomes a fun romp in the periphery territories! Partaking in a fun romp is ok right? Even desirable!
That's the level of propaganda they're going for. They're aiming to make being the imperialist desirable and the fun side to be on, which gets the audience onto that side, and batting for it years down the line after committing their identities to it. It's quite literally a mask for the intimidating presence of male patriarchal violence that you can't remove from the situation if you depicted male soldiers.
I believe in the Latino Belt as a concept of countries and regions banded together by its colonization by the Spanish Empire and their distain for that pathetic little country acting as a vestigial organ to western hegemony simply because it exists in europe.