Hello,
Not sure this is what you're trying to do. You can just select all the icons on the first Fence, click it and drag into the second fence. This will merge both of the Fences. The First Fence should be empty and you can delete it off. This only work for normal Fences. If you do the same steps on Portal Fences, it will copy all the selected files from the first portal fence into the second portal Fence.
Thanks
Basj,
Stardock Community Assistant.