there are no good examples. The basic premise in Linguistics these days seems tl be that all languages are potentially equally expressive. Trade-offs in one domain (grammar, lexicon, phonology etc.) afford advantages in another. Which means, there is no need to refer to Japanese at all.

You could equally refer to some slur in a lower register to then claim that this doesn't exist in your language and how it can't be translated either. So when Joe Biden said "SoB" on tape once, that was code switching; likewise, when Trump says anything it's all made up and coded and means something entirely different. However, these are bad examples if your target is a monolingual Japanese, obv.