$ids = ['16', '6'];
$productCollection = $this->_productCollectionFactory->create();
$productCollection->addAttributeToSelect('*');
$productCollection->addCategoriesFilter(array('in' => $ids));

return $productCollection;

public function __construct(
    MagentoCatalogModelProductVisibility $productVisibility,
)
{
     $this->productVisibility = $productVisibility;
}

$ids = ['16', '6'];
//$ids = ['16'];
$productCollection = $this->_productCollectionFactory->create();
$productCollection->addAttributeToSelect('*');
$productCollection->addCategoriesFilter(array('in' => $ids));
$productCollection->setVisibility($this->_visibility->getVisibleInSiteIds());
return $productCollection;