product_brand_add_form_fields

See hook in action

See this hook used in plugins:

Select Pluginwoocommerce.9.4.2woocommerce.9.4.3woocommerce.9.5.1woocommerce.9.5.2woocommerce.9.7.0woocommerce.9.7.1woocommerce.9.8.1woocommerce.9.8.5woocommerce.9.9.5woocommerce.10.0.4woocommerce.10.1.2