Hello, @Trends Bird Limited,
Basically, The thing is when a product is a variable product, so the user must select the product variant in order to add that product to the cart that’s why the popup comes up if you check the simple product without any variant in it you will never see that popup. It’s the default behavior of WooCommerce and you cannot change it without customization.
You can submit a request here https://www.8theme.com/taskboard/, so our dev team read it.
OR
If you want paid Customization services submit a customization request to WPKraken team.
Regards 8Themes Team.