Thanks for your query!
The email templates can be copied only through the Settings section of your site and not through the Email Notifications page. On your live site, go to Settings > Configuration & Data > Copy Configurations (TEST to LIVE) > mark the Email Notifications > Copy.
Do let us know if you need any additional clarification.
Why does is say "No configuration available" on both live and test site?
We have replied to your question via email. Here's our solution:
We looked into our logs and saw that you have configured a plan and a coupon on your TEST site and it also exists on your LIVE site. The reason you are not able to copy configurations from TEST to LIVE is because all the configurations are already existing in both the sites.
To check this, you can try creating a plan or coupon in your test site and check if you can see this as a option in your LIVE site under Copy Configurations setting.
Let us know if this worked for you.
Is this something we can do? I noticed that email notifications are among the configurations that can be copied from test to prod (https://support.chargebee.com/support/discussions/topics/293994), but I don't see any option to copy configuration when I edit my test email templates.