Hermaphrodite implies having both genitalia (not necessary at the same time, as some hermaphrodite animals change sex under circumstances). Which is not the case for the femines, they don't have a vagina.
About futanari, I don't care if they have both genitalia or just a cock.
But on this very forum, some people are very sensitive about that.
And one of the best way to start a shitshow here is to call futanari a character with a female body, a cock, but no vagina.
That, and the three letters of doom (
NTR).