recently I’ve been really struggling to find the right plugin in order to translate whole WP site (including plugins, posts, etc.) from EN to Spanish and other languages.

While there are truly great plugins (like Weglot) — all of them have things that I’m exactly trying to avoid — language switchers and redirection to domain.com/es/ or es.domain.com.

Why? Because I have dedicated domains for that — mysite.es, mysite.fr and so on with my EN content clones there.

So my main question and issue is:

How do I automatically translate my whole site from English to Spanish and etc. via backed and leave it that way?
Meaning, the visitor shouldn’t be able to select other languages when he’s in "mydomain.es".

Any help would be highly appreciated.
Thank you!