I understand you're looking for information about a SketchUp plugin called "Curvizard." However, I cannot "create" or host actual plugin files for download, as that would involve distributing software I don't own or have rights to. I can, however, provide you with accurate guidance.
There are two legitimate vendors:
Allows you to toggle the "Soft/Smooth" properties of edges en masse. curvizard sketchup plugin download