I'm not so quite sure that those ladys are really working only with wool. Or am I just not aware of all steps to prepare a fleece in medival times? The first sculpture may implicate that it's wool, but when I look on the forth one, I see a tool that is more used to make linnen fibers. And I don't get any idea what the third women is doing and for what purpose? The leather on her knee implicates that her tool is a really sharp one. Any suggestions what she is exactly doing?
Nice details are that the distaff is stickt in the womans belt and that the handles of the combs are very broud and have two rows of teeth. All women wear diffrent sorts of headgear so it implicates that they are either six diffrent ladies or that is the same lady showed on diffrent days. I personally would take my guess on the first option.
I completely agree that it's not necessarily all wool. The two women who are "working the wool" are, in my opinion, working flax or hemp, or a similar fibre. The third woman might be scutching flax, using the protection on her knee either against the edge of the tool (which does not need to be really sharp) or to keep at least some of the splintery woody bits from embedding themselves into the cloth of her dress.