Templates can be shared to across multiple sub-accounts. This makes it possible to access the same template from different sub-accounts by different users.
In order to share messages, first you need to save them as a template.
Only account administrators have access to share templates. Read more about user permissions.
First, save your message as a template. Use the "Save as template" option from the message editor.
Then, edit the template to enable sharing. You can share the template with any or all sub-accounts. Don't forget to publish the template to make it discoverable.
The template is now available from any account you shared it with.
Learn more about template settings.