El viejo dragon has some figures of medieval women bathing in various levels of undress. Other than that there are a few other companies out there that did produce some figures from the Manessa Codex and others that would fit pretty wel into a medieval setting.
There is a 14thc. French manuscript that depicts a group of women riding into combat with swords etc. It is from a 14thc. version of the Romance of Alexander and is supposed to represent the Amazons. But none of the women are wearing armor. It is also a medieval play on the reported rumor that Eleanor of Aquitane rode into Jerusleum armored up to intimidate the populace and muslims. Whether its true or not is lost in history.
There are a few accounts of women in fighting, but very few and far between. While the lady of the Keep was responsible for prep etc, while sir Dunce was off fighting a crusade for Urban it was more administrative than martial. She became a barganing chip and more often than not a means of securing alliances through marriage or promised sons or daughters.
Christian de Pisan did write several treatises on military tactics and it was a book that was used heavily in the middle ages to teach with. Including Henry V but it was also one of those that didn't get alot of press nor credibility (despite its success stories as a result) because it was written and compiled by a woman. She also wrote books on how to prepare cities for sieges and how women should act as those in charge of their holdings, domicile and properties.
Sure there are stories of women in combat. Bodiccia, Jean, Eleanor, Brigette Nielson, but those are exceptions. Just like every division didn't have an Audie Murphy. Camp followers were not only a way of life but essential for an army on the move. Not only were they the whores that entertained but they were also wives, daughters, cooks, seamstresses, nurses, sculleries, merchants, maids etc. Now on occasion in the 15th c. you'll read of accounts of women toting buckets of water to artillery pieces or helping with limber or other chores, but I'd be surprised to see a common account of their role as a "soldier".
The church forbade them, society did not allow them, and the soldiery didn't take them seriously. There is precious little documentation that can account for women soldiers in relation or to the scale that there is for men. Joinville, Villihardouin, Froissart, Roland, Chretien de Troy, Lull, Mathew Paris, De Charny were all chroniclers of ther times and wrote quite detailed accounts of combat, engagements, battles, tournaments, on knightly behavior etc. and they do not mention at all the presence of women as combatants. Lull in fact, despises them in this role and writes a whole treatise on the sin of woman carrying accoutrements of war and the degradation of knighthood and chivalry as a result if they should.
I suggest you look into some of Gerry Embletons (The Medieval Soldier in Photographs) books as well as some of the manuscrpts illustrations to see how these women are dressed and how they are depicted in these situations.