IIRC paste requires bitmap surface, but fusion now uses hwa texture (which has a function to rotate &stretch by hardware), it's slow to convert both type and it's also slow to stretch bitmap. So due to performance issue, I don't think it's possible in 2.5. I have made a custom version of picture object and implemented a paste with scale action, it's slow and useless in most cases, unless your object is very small and don't need to paste frequently.