How is a customer's email sent in their own language automatically?

The intended design is that email templates support multiple languages, so a customer's transactional emails (order confirmed, refund processed, etc.) are sent in their own language automatically based on their locale. Combined with the per-event email template system, this means communications match the language the customer shops in. *(This per-template multilingual behaviour is…

The intended design is that email templates support multiple languages, so a customer's transactional emails (order confirmed, refund processed, etc.) are sent in their own language automatically based on their locale. Combined with the per-event email template system, this means communications match the language the customer shops in. *(This per-template multilingual behaviour is noted in the requirements as an assumption to confirm — verify it's fully implemented before stating it categorically on the site.)*