People will be casting aspersions at Astorix next...
I have never come across a Hero (with capital H) in England, though I have seen the name a few times in Germany (where they presumably don't know what it means, as the German word for "hero" is Held, and "heroine" ought to be Heldin).
Usage: Greek Mythology
Other Scripts: ‘Ηρω (Ancient Greek)
Pronounced: HEER-o (English) [key]
Derived from Greek ‘ηρως (heros) meaning "hero". In Greek legend she was the lover of Leander, who would swim across the Hellespont each night to meet her. He was killed on one such occasion when he got caught in a storm while in the water, and when Hero saw his dead body she drowned herself. This is also the name of a character in Shakespeare's play 'Much Ado About Nothing' (1599).
It is in fact a female name anyhow.
As to whether a woman can be a hero rather than a heroine, that will depend on whether you feel they are also actors and not actresses, authors and not authoresses, waters and not waitresses.