4 th axe on Shapeoko 5?

As noted, there are alternatives to a 4th axis — and it is such alternative you would need to use in Carbide Create — two-sided/flip work would be the big one:

and see the recent discussion:

Doing more than 2-sides pretty much requires a 3D model which wants a 3D CAD program — we bundle one with the Nomad and sell it separately:

are you interested in learning how to use 3D CAD?

If so, that would make projects such as:

feasible.