Cola is a Spanish slur typically used against feminine non-heterosexual men and transfeminine people in Chile and Argentina specifically. It's also used against straight men, but only under the presumption that they happen to be queer.
History
The word cola appears to become popular in the 50s as a code word for homosexuals and trans women used by the police. It derives from the inversion of the word "loca" meaning "crazy woman". [1]