Code-Snippets-Functions/Execute a function on a child site/WooCommerce/set-custom-carrier-shipping-method.txt

add_action( 'woocommerce_checkout_create_order_shipping_item', 'action_wc_checkout_create_order_shipping_item', 10, 4 );
function action_wc_checkout_create_order_shipping_item( $item, $package_key, $package, $order ) {
    if ( isset($_POST['carrier_name']) && ! empty($_POST['carrier_name']) ) {
        // Get carrier number
        $carrier_number = isset($_POST['carrier_number']) && ! empty($_POST['carrier_number']) ? '(' . sanitize_text_field($_POST['carrier_number']) . ')' : ''; 
        
        $item->set_method_title( sprintf( '%s: %s %s', __("Custom Carrier", "woocommerce"), sanitize_text_field($_POST['carrier_name']), $carrier_number ) );
    }
}