Skip ZBrush - Use low poly only?

To note that I’m a beginner in 3D. The courses I have followed would walk me through modelling in Maya, sculpt and decimate in ZBrush, UV in Maya, bake maps in Marmoset, texture in Substance.

I am working on a realistic environment in UE to practice all that I’ve learnt. The buildings I’m making, however, do not necessarily require intricate sculpting. I wondered if I could skip ZBrush altogether?

How do I obtain a high poly count model, then? Do I even need one if I’m achieving the weathered/damaged look of a wall, for example, through Substance Designer? If I can indeed skip sculpting, how would pipeline look? Should I still bring the model in to use ZRemesher, decimate etc? Thanks!