Hello,

Try to use the Theme’s Layout Builder to create Custom Layouts for the Single Product page > and in that Layout you can add the product grid or carousel widget in the bottom of the layout and choose the data source “Related Product” and choose the list of product categories.
Screenshot for clarification:
https://ibb.co/BtP21qN

Here is the Guide to that: https://xtemos.com/docs-topic/single-product-page-builder/

Best Regards.