Hi there the ACF community 🙂
We did https://github.com/BeAPI/acf-options-for-polylang plugin to support this core-unsupported feature.
If you have some issues, inquirements, improvements or requests please refer to the github. We will be glad to help you.
@tomhermans, @zeshanshani note that we recently updated the plugin, so maybe your issue has been fixed. Please check it out!
Many thanks