Put it this way. If it's a fact down both flanks is better in a narrow diamond or narrow 4-3-3 I'll quit the game because that is the dumbest thing I ever heard and Nordeous need their heads checking because it is illogical and in reality is literally impossible thus meaning the game would be misleading to any player.
Please... Just stop lol. Mixed passing would work but is a waste, down both flanks would be void so you will basically be playing natural with no real build up or creativity.