I understand this is quite specific, but I have...
3x Monitors for display purposes and a monitor to control whats displayed through a video output window on the forward facing displays

the 3x Display monitors need to be duplication's of each other in portrait (and that works fine)

But what I need to be able to do is additionally split those duplicated displays into 3 virtuals on each screen and have 2 of those 3 virtual displays show the same video output window (That I can only generate once from my software.

But I am finding that 1st, my video output window does not truly recognise the virtual monitor when set to full screen, and will span all virtual's, and I cant duplicate/merge two virtuals together.

It is something I am able to achieve using a plug-in in my current video software, but I want to move away from this software, and thought Display Fusion may have been the answer.

I'm sure the answer will be that its not in the functionality, but I have to ask to be sure

Many thanks for anyone's time, and I hope that made sense

Andy