send a link when order is completed

You could use the purchase note field (in advanced product options). This will send any content/links after purchase in the order email.

I can see indeed. But this shows the link when its processing and when order is completed. I want it to be shown ONLY when it’s COMPLETED. Any way to do this?

For the time being, i am adding a note everytime a order is completed. But that is not handy as i get a lot of orders each day..

edit: i have products in variables, every product has another link. So this won’t work. I hope anyone knows a plugin that can do this?

Will this be the same link in every email? If so, you could just customize the order email template to contain the link.

Unfortanetly no. different link to each product.

I hoped there was a plugin that did let us add custom links or text to each product (also variabel). And we could choose that it would show on processing and/or complete.

You could customize the thank you template to include the link. On thankyou.php, you could do something like this:

<h3>Please visit the link below and complete the form:</h3>

 <?php
    foreach( $order->get_items() as $item ) {
	$_product = wc_get_product( $item['product_id'] );

	// Change Product IDs and URLs to match your products and forms
	if ( $item['product_id'] == 70 ) {
	  echo '<a href="yoursite.com/form_link_1">';
	} elseif ($item['product_id'] == 75) {
	  echo '<a href="yoursite.com/form_link_2">';
	} elseif ($item['product_id'] == 80) {
	  echo '<a href="yoursite.com/form_link_3">';
	} else {
	  echo 'Some default text of link here.';
	}//endif
    }//end foreach
?>