Hello,
In this case, HTML blocks translations behave in the same way as papes and posts do. When you have translations of pages in one language and do not have in another, when you enter the language you see no pages. So, first of all, you need to create translations. However, when you translate HTML you will do in a specific way.
For now, please refer the WPML documentation, create translations and as soon as you are ready to translate HTML blocks contact us so that we supervised you.
Here is the WMPL documentation https://wpml.org/documentation/
Best Regards