Some stores split products by both style and color - so “Basic T-Shirt in Green” and “Slim T-Shirt in Green” are all separate listings. Previously, you could group them by color, but there was no good way to also let customers switch between styles on the same page.
Now you can combine a Style group with Color groups to show both options as swatches. The Style group covers all products and uses pill swatches. Each Color group covers products of one style. On the product page, customers see both rows and can switch freely between styles and colors.
For setup details, see Swatches for products with multiple options.