This thread is resolved. Here is a description of the problem and solution.
Problem: The product description is not shown in the Translation Editor so I can't translate it. Solution: The cause of the issue is the use of mixed content inside the Description box. This happens when there are HTML code and shortcodes in the same content. To fix this you need to include the HTML code inside a visual builder element. Relevant Documentation: https://wpml.org/documentation/support/wpml-integration-with-page-builders-that-use-shortcodes/#an-important-note-about-mixed-content
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