Hi Bojan,
Did you mean change the entire content from the email tab to the language I want?
For example, the user register in Chinese. Wp-member should send the email content in chinese. Same as in English, if they register in english page, they will receive email content in English. I am using qtranslate-x plugin. My domain look like this:
English registration page:
https://mydomain.com/en/registration-page
Chinese registration page:
https://mydomain.com/zh/registration-page
I tried editing PO file. Nothing happened. Should I do edit some php codes?