The great thing these days is that technology and specifics available on guns make a shotgun fit a lady hunter a lot easier. Making for better recoil, better comfort, improved consistency and that creates an overall better experience shooting shotguns.
My go to gun is a Winchester Super X3. They are really lightweight. It is the fastest firing semi-auto on the market today.
Also, I usually pack a back up on big waterfowl trips. My Browning Gold Hunters are excellent shotguns too. I have a specific turkey gun with a 24" barrel but I use it for waterfowl also. Shorter barrel makes it easier for me to swing and especially manuver if I am hunting out of a boat blind, pit or ground blind.
There is a lot of great guns on the market. It all depends what fits and feels good to you.
Now over and unders...that's a whole other story in itself!