My suggestion on Subasekai's dual screen battle is simply shift your focus base on the light ball.
Consider the light ball is your biggest source of damage, keep your attention on it doesn't hurt.
And for the screens you have shift your attention away from, in Neku's case, just have him slide, lolo long invionci frame, and even better if you have Velocity Tackle on. Or you can prepare few full screen attack badge, twister is hand in cases like this. As for upper screen, just keep on guarding, or levitate up and down if you are using Josh.