Ok, got this working adding to this because I had hard time finding this. We’re also using the Avalara tax plugin for this, so I needed to use that for tax calculations. This is what I used:
$order = wc_get_order($order_id);
wc_avatax()->get_order_handler()->calculate_order_tax( $order );
$order->calculate_totals(false);
$order->save();