Problem: You are working on a site using ACF with WPML for multilingual support in English, German, Chinese, and Japanese. You have an ACF field named 'compatibility_info_content' set as a WYSIWYG in English and have created the same field in other languages with the 'copy once' option. However, content entered in the primary language is not being passed to other language versions for translation. Solution: First, ensure that your Field Groups are set to 'Not translatable' in WPML > Settings > Post Type Translation. After setting this, delete any translated groups and test the functionality again. If issues persist, consider setting the field groups to 'Different fields across languages'. This setting configures each field for translations created with the WordPress Editor.
Please note that this solution might be outdated or not applicable to your specific case. We highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix, and confirming that you have installed the latest versions of themes and plugins. If the problem persists, please open a new support ticket at WPML support forum.