Problem: You need custom behavior that falls outside the standard options of WPML. Solution: Since this involves custom work which is not covered by our standard support, we recommend contacting the theme author. They might be able to resolve the issue by using the code similar to what is used for WooCommerce stock.
Please note that this solution might be irrelevant if it's outdated or not applicable to your case.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 issue persists, please open a new support ticket at WPML support forum.