Hi,
In v6/v7, there is no OOB feature to support multi language emails.
As you mentioned, this is supported in ACS, and some translation mechanisms are available for v6/v7 web applications, but not for emails.
What can be done is creating conditional content from within the delivery content itself, where you'd specify a rule according to the recipient's preferred language, or country or so.
Hope this helps,
Florent