You find the code for the general tab in the file includes/admin/meta-boxes/views/html-product-data-general.php. In this file WooCommerce defined some do_action hooks. Maybe your plugin used one of them.
Hooks:
- woocommerce_product_options_pricing
- woocommerce_product_options_downloads
- woocommerce_product_options_tax
- woocommerce_product_options_general_product_data