Are there official translated versions for some of these Books/Scripts and if not are unofficial translations allowed?

For example The Art Of War by Sun Tzu doesnt have a german translation (as far as I know) which could lead to some problems, because someone might translate some words one way but someone else will translate it another way, making a run shorter/faster depending on what translation is used, it might even cause someone to translate a book/script in the least words possible, just to save some time, so I'm kinda just asking if the translation has to be an official one or if youre allowed to use translations by a fan/by yourself

I don't think it's possible for their to be an official German translation of the Art of War, given that at the time it was written the Chinese and Germans didn't even know each other existed.

That aside, so far for runs I've personally done of things that are originally in ancient languages, I make sure to specifically mention who did the translation of the version I'm reading mostly just for future reference's sake, but as of right now you're allowed to read non-author approved translations.

This does bring up an interesting question though of whether to require the 'official' translated version of a book if there is one available.