
Yeah, getting useful feedback is a major challenge for self-published authors. And I’d argue that “friends and family” are probably the worst people to give you feedback on your manuscript. Either they won’t give you honest feedback because they might hurt your feelings. Or they will give you honest feedback, which might result in hurt feelings on your part. It’s best to find someone who has enough detachment from you to proofread your work.
Personally, I try to get around this by inviting both alpha readers (for the first draft) and beta readers (for the nearly finished work) to give feedback for my manuscript. This seems to work fairly well, so far.

I am extremely skeptical that “AI” would do a good job with this. Old folk tales have a lot of local cultural, historical, and cultural context which the translator needs to take into account and explain. AI systems, in contrast, would turn this into a language they know best - which is largely Reddit posts of the last decade.
And the notion that “the Bible and Shakespeare have covered all plots” to be extremely reductive even for the English language. It gets rather insulting when you consider cultures outside of the Anglosphere, or “The West” in general.