I tried endlessly one day to find Matari PF directly referencing language and was unsuccessful. I didn't look in News articles, though. There are several areas of implication, though.
The Minmatar tribes evolved their own traditions over time, but limited communications between them ensured a few basic similarities in their social structure.
This line has always seemed relevant to me. Limited communication + few basic similarities in their social structure fits along with local languages, or at the very least dialects. And even in the case of dialects, IRL there are some dialectical differences that are so sharp that it takes significant effort for a nearby dialect to dialogue with them.
I'll keep on trudging through the PF looking for language references, there doesn't seem to be many.
Edit: Also, from the RP perspective, there would obviously be limitations for creating the language. It would be a fun project, but all you have to do is see how many Caldari players don't use or are annoyed with Napanii to see how far it will go.