With the G10 unique ability unlocked, Zombie will 'sacrifice' herself for two NS allies and automatically revive them (two total revives, not 2 per ally). This means you will want to kill a non-Zombie sister twice (or 2 different sisters once each) before targetting Zombie. Personally, I target Daka or Asajj because they tend to be easier targets for me early in a match.
Once zombie has spent her 2 'sacrifice' revives, go to town killing NS as you normally would. Make sure to not allow zombie to get 2 stacks of her buff by either not hitting zombie, or killing her a few times. of she gets 2 stacks of her buff, she's incredibly fast and can get out of control with her taunts. If you can, getting zombie to have 2 stacks of her debuff helps, because then she has 0% speed and will never move or taunt again.
One thing to note: Dont bother trying to stack Zombie's debuff on her before exhausting her 'sacrifice' revives. When she sacrifices herself for an ally, she loses all the negative debuffs from her unique.
Edit: Mine is a more generic way to handle NS, but FailingCrab's post sounds like it would work as well (or better) for your squad