The module is not shown in the product type

Thanks for reporting this. Please provide more information so that we can take a look at this.

The module adds the form via hook_form_alter, so no additional configuration is needed in case you are using standard display modes and standard Add to cart form. It does not differentiate between existing and new product types. In case you have some customizations on the product / variation / form (in your theme or module), you need to check these first.

As there is no response from the reporter, closing this. If this is still an issue, please reopen, or create a new issue. Thanks.