I think you'll need to set up a multi-lingual system allowing a user to define their language, then use the login addon to allow for templating of the registration emails into different languages.
You can use language tags in the email Tpl chunk, but MODX needs to have some way of knowing what the user's language is. You may have to turn off sending the email in the Register snippet and send the message yourself in a Register postHook after loading the correct lexicon language:topic.
If you have a way of telling the user's language before the Register form is shown, you might be able to use a custom snippet on the page to load the correct language file. Then both the form and the email might be in the user's language if both the form Tpl and the email Tpl contain MODX language tags.
Can you also use a user setting to set the language?
A cultureKey User Setting might be worth a try. Not all extras will check for a setting, and the setting might not be available at the time you need it, but it might work.
Thank you very much for your answers, I think I can get away with your work tracks.
How do I close this thread?
