Here are step I pasted again:
- Copy templates directory from wp-registration/
- Create a directory called ‘wpr‘ inside your current theme/Child Theme
- Paste the template directory into wpr directory created in the above step
- If you want to override specific template then just copy and paste only this template in the same directory structure.
So now you should have directory in your theme called ‘wpr’ with all templates. You need to open email/template.email.php file and make changes as per your need. But make sure you don’t touch top header PHP variables.