Display products from the primary category | related product

Hi Flo,

The selection of what goes into the related products is really something that is handled by woocommerce or your theme depending on what features it has.

Rank Math does not really have a specific feature for this.
You might need to do you own modifications on your own to get this working as you want.
There is a copy of how this can be done through with Yoast here https://wpexplorer-themes.com/total/snippets/yoast-seo-primary-category-related-products/

The method to get the primary category is used and then after they tie into the related products hook from woocommerce to alter it.

Rank Math’s hooks are listed here https://rankmath.com/kb/filters-hooks-api-developer/. Look for the hooks relating to breadcrumbs and the primary term. You could maybe use that to come up with your own version of Yoast one.

Alternatively you can use a plugin like shown here https://www.cloudways.com/blog/custom-related-products-in-woocommerce-store/ to set up the related plugins as you want.

Hope this clears things up.