Any pictures of exactly what you want to do. Different software does different things better than others.
Something like Fusion 360 may be very good for one thing, and very difficult for other things.
Never used FreeCAD, but most 3D parametric modelers are very similar. So Fusion 360 should be very similar. but Fusion 360 does a lot of other things that FreeCAD likely doesn't do.
It sounds, though, that what you want to do is relief models. Fusion 360 is probably not a good choice.
There are a handful of programs designed specifically for relief modeling, like Aspire, CarveCo (ArtCAM), and Enroute. All are expensive (to very expensive). I'm not aware of any free programs that have the same features.
But you can do 3D reliefs with something like Blender. You just need to use different tools, and possibly use different modeling methods.
A lot of the really good 3D models you see for sale are actually scans of hand carvings, or, are the results of incredibly skilled artists. Really high quality relief models are not easy to do.
While you may think you can make more money offering 3D models, keep in mind that they can take an incredibly long time to actually create, and then a LOT of time to actually machine them.