This product will explain the usage of customfield generic (dynamic) child variant. The base product is not ordable in this case.

Consider you sell products in different color settings: you want to change the color of the product by selecting a color variant.
Therefore dynamic child variants can be used to allow you different description, images, or product status for every variant of your base product.

Set up a new product, set price, add child products. Add created customfield generic child variant.
The child products are assigned to another category as the parent product for caclulation or like in this case to no category.
Do not tick the checkbox Display parent as option in this case.