Technically, the lore says they all have their own native language. It'd be easy to do Orcs and Elves since Tolkien has an elven lexicon and WoW and Gothic both have sturdy representations of language for Orcs. But I still fail to see the point? There is nothing about it that would immerse me more. Especially not with spanish speaking cat people and any form of french, polish, or any other languages native to...reality. I suppose the most practical way to go about it, though, would be to blend all the different versions of skyrim that are in other languages together....but why?