Do you have a pouch or RS? I don't have any experience with nursing and pouches. I did use a RS with DS2, who was about 3 months when I discovered BW'ing. At that time, I just stuck his legs out the side. Come to think about it, baby's legs do wrap around your body instead of sticking straight out. Can't see why you couldn't do this in a pouch. Does DD complain? If she doesn't, chances are she likes being squished (as do most NB babies)! FWIW, I didn't nurse in any type of sling the majority of the time. I usually just held him.
HTH
Kristin