When the Pinterest buyable pins feature was released to all Shopify users we were able to customize our own Pinterest product variatons to use in place of the 4 requirements (color, size, material, or pattern). We used to be able to change these 4 varints to anyting we wanted.
For example, for the Material varient I was able to add other varient options. Like when I sold citrine crystal clusters, I could have the customer choose which citrine clucster they wanted, so my Material varient was edited to say "Citrine".
I don't see where I can either take out these old varients I used to use to replace some of the Pinterest varients (like Citrine, US Ring Size, Cord Color, etc) or add new ones.