Language name display modiify

Hello,

I would like to modify the "Language display name" for both back-end and front-end. Where can I find the exact file for modification?

And this place

@Barlos, You changed user settings for admin panel. Check and adjust Configuration > Languages > Supported (here is link)

For the first picture. I would like to change display "中文(簡體)(tw)" to "中文(繁體)(taiwan)"

For the second picture, I would like to change display from "Tw" to "Taiwan".

Thank you in advance.

Attachment upload smoke test.