Variable product, sort related products by attribute

Hi!

My variable products have two attributes: size and color.

When user selects a color, I would like the “related products” to change accordingly to reflect the color change. This way, the red bra is suggested as related product to red panties or the white detergent is suggested to the white dress. I am thinking that it requires Ajaxifying the related products section.

Is this possible to achieve by functions.php snippet or plugin? Do you know of some good solution or where to look? Google searches have returned nothing of value.