This thread is resolved. Here is a description of the problem and solution.
Problem:
The client is working on a site under development and is unsure which REST API is required by the documentation. The WooCommerce Legacy REST API is incompatible with High-Performance Order Storage used in WooCommerce 9.x, and the client cannot use legacy WordPress posts storage.
Solution:
We confirmed that WooCommerce Multilingual is fully compatible with the WordPress REST API (wp-json), which is sufficient for managing translated WooCommerce content. The client does not need any other API, and it always refers to the WordPress REST API. For detailed instructions on setup and configuration, please refer to the following guide: Using WordPress REST API with WooCommerce Multilingual.
If this solution does not resolve your issue or seems irrelevant due to being outdated or not applicable to your case, we highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent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 further assistance is needed, please open a new support ticket at WPML support forum.
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