Google is testing product comparison on Google search results. I noticed this under related products.
Here I haven’t searched product comparison (Product A vs Product B). It seems to compare searched products with related products.
In this product comparison carousel; you can see the number of reviews, product specifications, product images, and an option to compare the product.
Here is the Screenshot:
Also under relatable products, there is an option to filter the products.
Here I searched Nikon D6, and there is a filter option like Full Frame, For wildlife photography, Nikon D Series, Nikon.
Here is another example: