Ways to create a tapered bevel cut?

All you could do in the free version of Carbide Create is draw things up in profile and do a series of no-offset contour toolpaths w/ a ball-nosed endmill — how smooth this would be would depend on your patience in setting up the file.

If you can generate a 3D STL you could use:

https://fenrus75.github.io/FenrusCNCtools/stl2nc/stl2nc.html

see: