2 of 2 people found this helpful
At email template level, this is not possible. It has to be done at email level.
If the content is semi-static (for instance an office address or some legal mentions), the easiest way is to use a snippet element in the template. It will only accept snippets as a content and you can even assign a default snippet to the zone. Then you can make the snippet dynamic so that it automatically displays the proper value.