Ooooh, that's a neat idea!
Never liked wooden mannequins, lol. I have one sitting on my shelf, but that's pretty much all he does: sitting on the shelf and collecting dust XD
For pose references, I got myself a Bodykun + Bodychan and they're pretty useful, though definitely more expensive than a Barbie, at least where I live. I also got myself a Vindoll... not specifically for drawing, BUT it does make for a very nice mannequin if you want to. It has a more realistic body, it's light despite its size and very easy to pose. Sadly, only the male body is available as of now and the whole thing is pretty damn expensive. I got one because I loved Granado's resin dolls and one of his Vindolls had the same face sculpt as the doll I wanted for half the price... honestly, if I had to buy it solely as a mannequin, I don't think I would have bought it XD there is a Vindoll frame that costs a lot less, though! Being only a frame, it's not as realistic as the full doll, but... for pose references, I think it could work pretty well? 