Some e-commerce sites will group similar SKUs together on their product listing page. For example, Macy's would group the same modeled stand mixer with different colors together and just show different color options within the SKU box:
Other e-commerce sites will have similar SKUs spread out (ungrouped) on their product listing page. For example, these same modeled headsets on Amazon:
From the UX perspective, which method is better at converting browsers to paying customers?
Please back up your claim with data or research, thanks.