1. $productCollection = $objectManager->create('Magento\Catalog\Model\ResourceModel\Product\Collection');
2.  
3. $productLink = $objectManager->create('Magento\Catalog\Api\Data\ProductLinkInterface');
4. $collection = $productCollection
5. ->addAttributeToSelect('*')
6. ->addFieldToFilter('visibility', 4)
7. ->addFieldToFilter('status',1)
8. ->addAttributeToFilter('kolekcja', ['notnull' => true], 'left')->load();
9. $array = array();
10. $i = 0;
11. $linkData = array();
12. foreach ($collection as $product){
13.  
14.  
15.     if(!count($product->getUpSellProductIds()) > 0):
16.  
17.     $productCollection2 = $objectManager->create('Magento\Catalog\Model\ResourceModel\Product\Collection');
18.     $collection2 = $productCollection2
19.     ->addAttributeToSelect('*')
20.     ->addFieldToFilter('visibility', 4)
21.     ->addFieldToFilter('status',1)
22.     ->addAttributeToFilter('kolekcja', $product->getKolekcja())
23.     ->addAttributeToFilter('producent',$product->getProducent())->load();
24.  
25.         if($collection2):
26.             $r = 1;
27.      
28.             unset( $linkData );
29.             foreach($collection2 as $product2):
30.          
31.                echo $product2->getId().'</br>';
32.                $productLink = $objectManager->create('Magento\Catalog\Api\Data\ProductLinkInterface')
33.             ->setSku($product->getSku())
34.             ->setLinkedProductSku($product2->getSku())
35.             ->setPosition($r)
36.             ->setLinkType('upsell');
37.         $r++;
38.         $linkData = $product->getProductLinks();
39.         $linkData[] = $productLink;
40.         $product->setProductLinks($linkData)->save();
41.             endforeach;
42.    
43.         endif;
44.  
45.  
46.     echo $product->getName();
47.  
48. endif;