Add-on extrude / sweep mesh edges along mesh edges?

so if I would set it to “0” then it would not be scaled?

not exactly, it’s a multiply value set to 1 to get a unaltered proportional scale, set to 0 it’s going to break the value, in practice is very simple:

Edit: you would like to scale the profile also along the “height” axis?
This Is feasible, I can just add a 'profile height parameter" but It will uncheck automatically the fuse option: like you see in the video you can use the sweep also to ‘sculpt’ the geometry.
The height parameter could be also expressed in absolute measure, I ll make a test, It’s Just a matter of add the parameters exposed in the UI.