In the Scramble For The Throne arc of Kinnikuman, one of the five impostor Kinnikumen is a Mexican wrestler named Mariposa (Butterfly). It's supposed to be a reference to his graceful, high-flying techniques, but in an anime with muscular, scantily-clad men grappling...
In general "XXX" in Japanese just means "(blank/variable thing)", but in English speaking language generally means something to do with pornography or moonshine. One work that could suffer from this trope is ×××HOLiC.
Panda and the Magic Serpent, Japan's first color feature animated film, has an English dub that sounds quite liberated for the 1950s: "There was a gay festival in the village. Everybody was celebrating."
In the school arc for Black Butler younger students who act as servants for older students are referred to as "fags". Which is probably where the association with homosexual men came from in real life as this system was practiced in all-male boarding schools in England.
The English dub of Chrono Crusade uses accurate 1920s slang which causes this to occur.
Done intentionally in Full Metal Panic!, where at one point Tessa (a submarine captain who is posing as a junior high student at the moment) says she's got experience in "the water business", which is Japanese slang for prostitution. Kaname responds with a muttered "That's kind of a poor choice of words..."