Magento2 : Parent category load child category's product too

Question

In my store parent category load collection of its child category also.
I can solve it by Is Anchor to "No".
But by doing this Filter is not coming in the left bar so it is not the solution of my problem.
How can I load the products which I assigned to the category itself?

Answer 1

I solved this for Magento 1. You can see the answer in here.
You can try a similar approach in M2. Not sure it will work, though.
The anchor flag is taken into consideration in the Magento\Catalog\Model\ResourceModel\Product\Collection::addCategoryFilter() method.

Maybe it will work with an around plugin, where you set the anchor to 0, then execute the initial method and set it back to the value it was before.

Something like this (untested):

public function aroundAddCategoryFilter(
   \Magento\Catalog\Model\ResourceModel\Product\Collection $subject,
   callable $proceed,
   \Magento\Catalog\Model\Category $category
) {
    //remember the category anchor flag
    $anchor = $category->getIsAnchor(); 
    //set anchor to 0.
    $category->setIsAnchor(0);
    //execute the original method and remember the result
    $result = $proceed($category);
    //set back the anchor flag on the category
    $category->setIsAnchor($anchor);
    //return what the original method returned;
    return $result;
}

More info about creating a plugin in the official documentation