A: Hello

Unfortunately, it is not possible to deactivate the plugin externally.

The only thing you could do is purchase the plugin under your own name and, in case you can no longer access the backend, request to have the license key received after the purchase deleted and a new license key generated.

This way, the plugin using the old license key will no longer have access to updates, the important thing is that the purchase is made under your own name.

Hope it helps

Best regards

Alex