How you can change language for users
You can set the language in which users receive emails and see courses by using the 'Change language' setting after selecting users on the Users page.
How users can change their own email language
The language in which emails are sent to end users is always the same as the language in which the user takes their courses. Therefore, if a user changes the language on their courses using the drop-down, every email they receive from thereon out will be in that language.