A nice tutorial on using Path workbench included in FreeCAD

Do you know of Freecad works for plasma cutting with freecad and linuxcnc?

I do not think so, and i never tried.
I use strictly Inkscape for plasma machines, it is easy to use and works perfectly fine, except for nesting that requires dividing cuts into layers and groups, so a bit more fiddly and i do not bother with it, it is easier for me to just edit the resulting gcode and move stuff around.

Works great but I did have to create a post processor for qtplasmac; see

github.com/tomsgarage/freecad-qtplasmac-postprocessor

Thats cool. I passed the plasma post processor on to Brad (sliptonic) wondering how it can get into freecad. He's the Freecad CAM man.
A lot happening here. Brad put a PR into linuxcnc for MTconnect and he now is querying Linuxcnc machine specs from freecad CAM.
5 axis  3 +2 will be in the next release.
And a blog post from Brad about 5 axis.  sliptonic.com/posts/machines-cheap-toolpaths-not/