I haven't been able to try this mod myself, but a friendly internet person reports that it works as advertised! However, he notes, it applies only to barmaids and does nothing for the governors' daughters. This further improvement I leave as an exercise for the reader.
From the page: "This mod gives the barmaids less revealing clothing, making the game even more child-friendly. It replaces the clothes of barmaids in the taverns of all four kingdoms and pirate havens."Modesty Go! (modesty mod is at the bottom of the page)
Thanks, The Serpentine Cougar, for making this mod!