This should be easy to do.
First thing I'd recommend is to get up to speed with button editing by watching the video tutorial (it's video only, no headphones required).
Then have a read about the Copy command in the Opus manual under the "Opus Raw Commands" section.
The command you want will probably be something simple, like
Copy To=""
Once you understand all of that you should be able to create a button, or right-click context menu entry, for each destination that you may need to copy to.
You could make it more advanced by automatically selecting the source files but we can talk about that later, once the basics are working.