so, would this be the one time to learn poems as a female character? or is the marriage proposal the same for all lords, as separated from ladies, regardless of gender?
The AI regards all Lords as male (since there are no female Nobles in-game, at least untill you make them Noble); It doesn't consider the possibility of female ones. So, if you want to marry an (female as well as male) ennobled companion, it works the same as courting 'normal' Lords.