This thread is resolved. Here is a description of the problem and solution.
Problem:
If you're experiencing an error message '[Unproccesable_entity] The requested action could not be performed, semantically incorrect, or failed business validation' when attempting to purchase via PayPal on your website, and the issue stops when deactivating WooCommerce Multilingual & Multicurrencies, this might be due to a known issue.
Solution:
We recommend downgrading the PayPal plugin to version 2.9.0 as a temporary fix. This is a known issue related to currency handling in WooCommerce with PayPal. For more details, you can check the documentation here: https://wpml.org/errata/woocommerce-paypal-payments-error-cannot_mix_currencies/
If this solution does not resolve your issue or seems irrelevant due to being outdated or not applicable to your case, we highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent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. Additionally, if you need further assistance, please open a new support ticket at WPML support forum.
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