The WooCommerce Eu Vat & B2B (WCEV) seamlessly integrates an additional EU Vat Number Field into your WooCommerce platform. It will be dynamically shown during the checkout process only if the selected billing country is part of the European Union. The plugin also offers several other options, like a way to validate the field, make it mandatory or remove the Taxes if a valid Vat number has been entered. Optionally you make the registration process available only for businesses (B2B) with a valid Vat number!
info: https://codecanyon.net/item/woocoomerce-eu-vat-field/19463373