I was wondering because the coloured wires plug in behind a VGA input connector. Would a DB23 to VGA Amiga custom cable be able to plug from Amiga out into VGA input socket? Otherwise what's the Input VGA connector on the board for?
I agree, That should work The adapter just converts the wiring but no scan doubling happens there. you would need a 15Khz capable monitor, Hard to find so still needs to be doubled.
However you will have a lot of stuff sticking out the back and would be cleaner to just solder on your own connector.