Quote - I particularly want accurate cloth flow, and an easy way to know how to cut the cloth the same as the images

Neither Poser nor DAZ|Studio will give you that - you would really need a proper fashion CAD program for that (and big bucks...). They could help you with the visualisation, but as Pakled says, you'd need to model your design in 3D first. Unfortunately the requirements for making an image are not the same as those for designing clothing when it comes to the cloth cutting etc.