Reply To: variable product

Hello,

You are trying to add custom attributes. You need to create and add global attribute in Dashboard > Products > Attribute. https://docs.woocommerce.com/document/managing-product-taxonomies/ and https://docs.woocommerce.com/document/variable-product/

Here is the instruction on how to configure swatches for variable products https://xtemos.com/docs/basel/attribute-swatches/

Best Regards