This is a rarer use of "come out in" and "come out as."
"When I use Google Translate and set it to Korean, things that I type in English come out in Korean."
"I haven't been speaking much French recently, but I've been speaking a lot of Chinese. When I met a French person yesterday, I intended to speak to him in French, but my words came out in Chinese instead."
Here, the speaker is humorously imagining that "Moron" is the name of the language that morons speak. The speaker is imagining that "Moron" is a language like French, Spanish, and Korean. When you are in love, you attempt to say intelligent things, but your brain automatically translates everything you say into the language of "Moron."