I'm a Zbrusher too!
Zbrush and Blender operate via what's known as polygonal modeling. This works with XYZ coordinates making up points that form triangular faces to represent the 3D geometry you're modeling up. While software packages like Fusion 360, Solidworks and SpaceClaim operate via what's known as solid modeling. With solid modeling, mathematical formulas are used to describe 3D geometry you're modeling up. So, the good thing to know is one can convert a solid model to a polygonal model but it is extremely difficult to convert a polygonal model to a solid model. Consequently, when you're working with Zbrush or Blender and want to export 3D geometry to edit in Fusion 360 you are going to run into problems. Fusion 360 can import something like the 3D printing industry standard STL ( Standard Tessellation Language created by the inventor of 3D printing Chuk Hull and his company 3D Systems) yet in most cases it won't be very usable as a solid model.
What I mean by not very usable is, well, when you do solid modeling for a while you really really appreciate that all of those triangles are GONE!
You get used to working with perfect looking geometry and the software mostly only works with perfect looking geometry. So, when you import something like a polygonal model in the way of something like an STL file and try to convert it to a solid there will be problems with converting all of the facets. Generally, you'll end up with a solid model that's not very usable as a solid model because of the imperfect conversion of all of the facets.
So what to do? Just keep it in mind while working to try to keep the workflow going from solid model to polygonal model, not the other way around. So let's say I was going to make something like an incense burner with a nice dragon motif and I wanted it to have a cover that could open and close via a hinge. So, I'd start off in Zbrush doing the sculpting and then I would design the hinge with all of the desired clearances in Fusion 360 and then I would export the henge into Zbrush and attach it to my sculpture and from Zbrush I would export as an STL via the 3D print exporter for 3D printing in something like brass.
Except I don't use Fusion 360 most of the time. I mainly prefer using the free reduced function version of SpaceClaim called DesignSpark Mechanical. If you'd like to try SpaceClaim / DesignSpark, get the first version that has the blending function enabled, which can found
here for 32 bit and
here for 64 bit. In later versions, they removed the blend command. Comparatively, Fusion 360 is a
full package that can be used for free while DesignSpark Mechanical is free but has
numerous functions disabled compared to the commercial version. Sometimes one runs into situations where one wishes that the complete functionality were available, like for example it doesn't allow the 3D mirror command to be used. However, I use DesignSpark Mechanical because it's overall functionality is lightyears beyond everyone else! When I can afford the commercial version one day I'll most definitely buy it!
When I use Fusion 360 I think it's ok overall, but I feel like I'm using a CAD package from the MSDOS (Microsoft Disk Operating System) days and it's just plain clunky and awkward. On the other hand, had if I never used SpaceClaim before I would think it was pretty darn good!