you will find option to change in default email template from your admin panel “General Settings > Email Template”, you have to give content for all available languages to make it multilingual.
few things to notice here, you will find three key here listed below
- @username: this will retrieve username if mail send to any registered user
- @message: this will retrieve message given by you or user
- @company: this will retrieve your site details you put it in “general settings> basic settings”
that’s all for email template.