Hi,
No there is actually no option to order by clicking on the label/header. You can do it by editing the view "product / listing_table" and the file "components/com_hikashop/views/product/view.html.php" in the function listing.
You will have to set a link on the label to refresh the page and set a get variable, for example "sort_name", and in the view.html.php file edit the ORDER BY in the request to change it by the value received with the get method.
Some knowledge in PHP are required.
You can also use the custom fields to do that, using the "sort" value.
