As a female Fitzhenry doing the Fitzhenry One Name Study, this is a question that has vexed me for a long time! And the past is very much a foreign country where surnames are concerned in Norman and Plantagenet England.
The previous answers and comments have shown what a minefield this is.
Men who had a personal rather than hereditary Fitzhenry surname (literally the son of Henry, or Henri if it was really early) float around in my database connected by blood line but unconnected by name to their parents or children, rather like Icelandic naming conventions today ("sson" and "dottir").
Women at that time spent their lives as possessions of their fathers or husbands. Hence descriptions such as (Christian name) daughter of Sir Y or wife of Lord Z. Some independent single women may have had descriptive surnames but these would have been purely personal and would not have been hereditary. And they wouldn't have had them at birth.
The written female version of Fils de or Fitz de would be "Filia de"
From my own personal database point of view (highlighted showing what I do offline), I put the father's Fitzhenry surname in the daughter's surname field, but this is more to keep the database tidy than for historical accuracy for pre-hereditary surnames, and I wouldn't do this on Wikitree.
If the family has got to the stage of hereditary surnames (which will vary depending on the family and the place - Wales was a very late adopter of this), then using the father's surname for the daughter is fair game I think, especially if I can find a parish record that gives her a surname.
If Wikitree would allow one to leave LNAB blank, or enter the name at birth as "daughter of X" this would be perfect.
I would say "hope this helps" but it probably hasn't... sorry!