Reading in the q&a forum, I see a lot of the same questions about translations , but no solutions that work. I still have these translations issues, with every template of your plugin. I translated with loco translate, no luck. WPML is a too large plugin for a few words.
I believe that passing on the problem to others like loco translate and wpml isn't the right way to handle a problem of your plugin.
I have tried loco translate. It works for many plugins, but not for the email customizer. I emptied cache, reinstalled loco translate and all, but no translations visible.
Isn't it handier to make your own .mo .po files, or other solutions so translations go easy for all users? And you will have less questions, better rating and more time for yourselves 🙂
I hope for a fast solution.
Please have a look at our help video Translate Email Customizer for WooCommerce using Loco Translate