Where can I find the magento extension's package with Hyva-compatibility to install it?

You can find the module compatibility package with Hyva theme in the "suggest" section of composer.json and install it. (Note: the compatibility is available as part of an active product subscription or Support Subscription).

Note: Most Hyva-compatible extensions require the GraphQL package, so install the GraphQL package from the "suggest" section in composer.json for compatibility to work correctly.