Hello,
Something like this
$order = new Order((int) $id_order);
$history = new OrderHistory();
$history->id_order = (int) $order->id;
if ($order->current_state != (int) $id_order_status) {
$history->changeIdOrderState((int) $id_order_status, $order, true);
$history->addWithemail(true);
}
Thank you