Because I just lately studied that one portion of the Tanach, and because I seem to occasionally not care what I put here, I would like to list the occasions any type of language gap is mentioned in the Tanach from memory. The best part of this is that no one is likely to correct me if I'm wrong, but alas, that is also the worst part. I'm free to be as wrong as I want.
First time would be every time the list of descendants of one son of Noaḥ is concluded: from those were split the nations to their tongues or something like that. Did I mention I'm doing this from memory? Anyway, I'm counting it once because it gets repetitive.
The Tower of Babel. Kind of obvious. "Let us go down and mix their languages" and all that.
Yegar Sahaduta/Gal‘ed. You'd think living with your uncle/father in law for twenty years will make it so you both speak the same language and call places the same name. Apparently not, because Lavan and Ya‘akov insist on giving that rock pile names in two different languages.
"But they did not know that Yoseph understands them, for there was a translator between them". At least, if that's what Melitz means, which seems likely in context. Yosef and his brothers in Egypt, back when they don't know it's him.
Next time anything of the sort is mentioned would probably be "nation you know not the tongue of", but I'm not sure if it's in the cursed in Vayikra or Devarim. If it's Devarim, then I suppose the various names for mount Ḥermon count as well, so:
Various names of Mount Ḥermon. And of the Refa’im. Might be a language thing, might be something slightly different, since most of those languages are mutually comprehensible. But it's probably language.
As far as I remember, the next one would be the one I just learned: Ravshake coming to Jerusalem to scare everyone in it, the ministers of Hezekiah asking him to speak Aramaic and not Hebrew (si as not to destroy the morale), and he doesn't care about it at all. Fun stuff.
Then you get the one verse in Aramaic in Jeremiah, which I'm pretty sure is singular. We're not getting another language until the Ketuvim.
In which we get "so the Chaldeans spoke to the king in Aramaic..." In Daniel, at which point it turns into Aramaic until the author recalls to use his Hebrew.
‘Ezra and Neḥemyah also have fun Aramaic portions. Mainly ‘Ezra.
Forgot the book of Esther - the one tine every nation gets stuff in its language. So that's acknowledging the language barrier I suppose.
I believe that's it. Correct me if I'm wrong. That would be eleven times - more than I thought, but I still think it's a surprisingly small amount of times all things considered.