They both have the exact same properties, simply aesthetic differences. Why is Prism grouped with Master, Savant, and Claymore when it is simply a Katana reskin?

Dev said that prism sword might have gameplay related differences so it's not allowed in the normal category. He couldn't confirm that it's just a reskin without any other differences.

Dev just confirmed that there are no gameplay related differences. Prism will now be allowed in the "normal" category with the Katana.