There is much debate amongst those remaking historical clothing about the use of buttons on dresses. Here is one researcher’s findings:
Until the late 18th century, buttons are rare on women’s dress. In the few earlier pictures, the direction often can’t be determined. At least I’ve found one 14th century example where the buttons seem to sit in the right-hand edge (i.e. the “male” side), and two ditto examples from the 17th century. In the late 18th century, we find buttons on female dress relatively often, e.g. on comperes, jackets and redingote dresses. In every case, the buttons sit on the right side. In the 1830s, buttons are rare on women’s clothes and evenly distributed between right and left, then nothing until the 1850s. During the 1850s, left slightly outweighs right. From the late 1860s on, buttons are quite common on women’s dress – all left.