I still think shisui should be placed first, for one he has chaos and remove buff/shields and still hit multiple units... so he can effectively chance an interrupt

itachi anbu can't, plus itachi passive of giving shisui a double atk, so you would want to stack shisui instead of itachi anbu esp when shisui norm atk hits 2 units really hard.

Ahh no ChrolloLucilfer, auto barrier like beginning of turn buffs/shields depends on total initiative of entire team...

The higher your total initiative the later your preparation start off, which will cancel off the opponent auto barrier if your preparation go second.