Copy From / Copy To

Hi,

Is it possible to use Copy From / Copy To functionality for Add-on Screens?

For Example:

As of now, PO has a copy to for GR-PO, and GR-PO has a copy from for PO. I introduce a new screen for subcontracting DCs alone, for which I need to select a few PO and move the data to my DC screen. Can I add my screen name (DC) in Copy To Menu of PO? Similarly, is it possible to add the Copy From button to my screen, and add PO there?