mondo

Mondo can translate into (almost) every language the names of the world's
scripts, languages, territories (including countries), and countries'
subdivisions.

Translation happens locally, in your machine.

For that, you'll need data from Unicode Consortium's CLDR:
  https://en.wikipedia.org/wiki/Common_Locale_Data_Repository

That data is available for you to download free of charge, and is licensed
under the free and open-source Unicode-3.0 license.

For all the details, please do see the README

Open it easily with:
  (find-file-read-only "README.org")   <--- C-x C-e here¹

or from any buffer:
  M-x mondo-see-readme

or read it online:
  <https://flandrew.srht.site/listful/sw-emacs-mondo.html>

¹ or the key that ‘eval-last-sexp’ is bound to, if not C-x C-e.