VeriFactu en WooCommerce.
Un hook de WordPress y cada pedido acaba en AEAT.

<?php
// wp-content/mu-plugins/cofactu-verifactu.php
add_action('woocommerce_payment_complete', function (int $order_id): void {
    $order = wc_get_order($order_id);
    $lines = [];
    foreach ($order->get_items() as $item) {
        $subtotal = (float) $item->get_subtotal();          // sin IVA
        $tax      = (float) $item->get_subtotal_tax();
        $lines[]  = [
            'descripcion'    => $item->get_name(),
            'cantidad'       => (float) $item->get_quantity(),
            'precioUnitario' => $subtotal / max(1, $item->get_quantity()),
            'tipoIva'        => $subtotal > 0 ? round($tax / $subtotal * 100) : 0,
        ];
    }
    $nif = $order->get_meta('_billing_nif');                 // el meta de tu plugin de NIF
    wp_remote_post('https://api.cofactu.com/api/webhooks/ecommerce-orders', [
        'headers' => [
            'Authorization' => 'Bearer ' . COFACTU_API_KEY,   // define() en wp-config.php
            'Content-Type'  => 'application/json',
        ],
        'body' => wp_json_encode([
            'platform'        => 'woocommerce',
            'externalOrderId' => (string) $order->get_id(),
            'client'          => $nif ? [
                'nif'          => $nif,
                'nombre'       => $order->get_formatted_billing_full_name(),
                'email'        => $order->get_billing_email(),
                'direccion'    => $order->get_billing_address_1(),
                'codigoPostal' => $order->get_billing_postcode(),
                'ciudad'       => $order->get_billing_city(),
                'pais'         => $order->get_billing_country(),
            ] : null,                                           // F2 simplificada
            'lines' => $lines,
        ]),
        'timeout' => 15,
    ]);
});