Add Localization Module

Hello!
Our goal is to enable users to login to the /cms backend, and be able to select “Japanese” as their language. This would enable CMS users to see labels presented in Japanese.

Referencing this article: https://documentation.bloomreach.com/14/library/concepts/security/configuring-the-login-page.html

I am understanding that you can enable languages for:

English, French, German, Dutch and (simplified) Chinese

What I am looking for is instructions on how to create or enable a localization module for Japanese.

We are specifically looking for help localizing the CMS interface. We do understand how to localize CMS component labels.

Please help!