If we're talking about an in-game addon (.lua) then making sure you save your file as utf8 should suffice for saving and looking up keys without escaping characters.
That is save as [blāblā] and look it up the same way.
If you have a web interface parsing saved variables, or you need to copy paste from in-game to a web site or some other interaction of the kind, provide more information about what exactly you're trying to accomplish and in what environment
