You're free to use DAZ assets to make whatever you want, and post it/sell it/do whatever you want with it, as long as you don't provide the actual 3D mesh. By that, I mean that for you to use DAZ models in say Unity, or similar realtime 3D engines, you need an interactive license, which you can buy separately in the DAZ store.
For regular artwork (renders, images), you do not need any specific license, you can post whatever you want (as long as you follow the rules for whatever site you're posting it on, of course)