I have never tried this, but I suspect it is possible to create a "motion envelope" of the new gear geometry. The "problem" in this case, is that the motion envelope is fixed relative to ground. So you will have to define the motion of your parts so that one of them, "female" is fixed to ground, and the other one has its motion defined relative to the fixed part. (*testing*). It turns out the resulting geometry (I would think), is too coarse, see below. Note that the resulting "toothed" surface is the negative of the desired gear wheel.
Motion model used:
