Well, the main issue here lies in how arthropods work: their growth is directly related to the amount of oxygen in the air. You see, arthropods have respiratory systems that basically takes oxygen directly to their tissues. That means their muscles virtually don't tire out, but it comes at the cost of being dependent on how much oxigen there is. In the case of insects, as their tracheas work through the diffusion of gasses, once they start to grow, it starts to become a problem, as less oxygen gets through, until they reach the size limit, which for land arthropods is that of a crustacean, the coconut crab, and, despite being strong enough to snap a bird's wing, they're rather slow. During the carboniferous earth, as oxygen was available in much higher concentrations, we could have animals like the 2 meter long arthropleura or the giant dragonfly Meganeura, but nowadays, not so much.
So basically to make insects grow without slowing down you'd need to either 1- bioengineer them to have entirely different respiratory and circulatory systems to match more those of vertebrates, allowing for bigger growth, or 2- alter them to allow for indefinite molting, raising them in oxygen rich environments and sticking oxygen tanks to their breathing apparatuses once they had to leave to the outside. Neither sound that effective for mass production. I'd recommend instead doing what scientists already are doing: researching insects and other arthropods to integrate their special abilities into robots, such as drones that employ the dragonfly flying abilities or rescue robots capable of compressing themselves as roaches. Those are easier to produce, take less time to be ready and don't need oxygen tanks stuck to them
Note: to use normal sized insects, it's already being considered in the form of cyborg beetles and roaches, maybe with more technological, smaller implants. However this can be considered unethical, as you're basically forcing the animals to do what you want by essentially hijacking their bodies, and the concept of being a passenger aboard your own meatsuit is quite the theme for a Sci fi horror story in itself.
Edit- sorry, it is true that tracheas are exclusive to insects and other arthropods have other different types of respiratory system, and my answer seemed to say so otherwise, however I decided to focus on insects in this question simply due to their wide distribution, the already existing research being conducted on them for your purposes and the fact they're the only arthropod group capable of flight.