Trifecta Crop Control is primarily intended for use on soft bodied pests. It will kill a stinkbug if it is sprayed directly on its underbelly, in the thorax region. But as a general rule, it there are better options for killing stink bugs if you have an infestation.
As far as prevention is concerned, most pests are repelled by the essential oils in our formula. If you apply Crop Control as a preventative, your plants should remain pest free.