Can’t really see any benefits of switching from ZBrush to Blender if you already have a license. Blender has absolutely nothing superior to ZBrush in terms of sculpting and is losing at any point.
But in terms of starting, Blender is a good option, because it’s still pretty capable and of course is free. Another overall benefit is that you can limit your pipeline to a single modeling package with blender, though I still recommend using something else for texturing, like substance painter, for example.
