How to show product variants in your advice
Use the product variant feature to group product variants in your product data. Variants are a group of similar products that only differ from one another by product details like size or color.
Enabling variants
1. Go to "Settings -> Feed" and click "Enable variants" to enable the Group and Color feed mapping properties.
Mapping your feed properties
1. Go to "Feed" in the left navigation.
2. Go to the "Mapping" tab.
3. Scroll down and map "Group" to the feed property by which your product variants are grouped.
If you're using a Google Shopping feed, you should probably map this to the item_group_id.
4. Next, map "Color" to the feed color property.
Results
Once everything is set, your products will now be "grouped" by the mapped "group" property and color variants will be shown for each product card.
Clicking the color variant thumbnail will switch the card's information to that variant's information. When you then click on the card, you will be redirected to that variant's product page.
Documentation