Note: We highly recommend creating a child theme when you are editing theme template files. You can learn about creating a child theme in here.
You might notice that your products in the shop pages created with the shop module don't have a "Add to Cart" button, if you want to add that, all you need is to add this code in the functions.php file of the child theme.
// Add "Add to Cart" buttons in Divi shop pages
add_action( 'woocommerce_after_shop_loop_item', 'woocommerce_template_loop_add_to_cart', 20 );
Alternatively, if you don't want to use a child theme, you can install and activate the following Code Snippets plugin and open the WordPress Dashboard > Snippets > Add New option and add a title to the code and Codes under PHP codes and click on the Save changes and Activate button from the bottom left.
Note: Just so you know, we can't promise support for any third-party plugins regarding compatibility or can't take liability for any security concerns.