A phallogyne is basically a woman with a penis. This is a catch-all category that includes (but is not limited to) futanari, “shemales,” and transwomen who have had genital reassignment surgery. “Phallogyne” can refer to any person who has basically a woman’s body but also has a penis. How she got the penis (naturally, surgically, by magical transformation, etc.) does not affect her status as a phallogyne. Whether there are testicles or not does not change the fact the person is a phallogyne, and whether she has a vagina or not in addition to the penis does not change her status as a phallogyne. Defining the term as widely as possible, “phallogyne” might also include male to female transvestites.
“Phallogyne” is not as specific a word as some of those used above, but that in many contexts makes it more useful. Also, some words like “shemale” have offensive overtones. “Futa” is also problematic because the futa in a sense seems by now almost to be by definition a kind of sex object. “Futa” connotes someone who has virtually no humanity beyond the purely sexual dimension. “Phallogyne,” on the other hand, does not imply that if one is a phallogyne one is nothing but a phallogyne and has no real self or identity beyond that.
Personally, I prefer to use the word “phallogyne” in reference to my own work, because it tends to be more accurate and because it is bereft of the negative connotations of some of the other words used. For an erotica writer, however, this creates a marketing problem. “Phallogyne” is gradually becoming known as a term, but is not yet known widely enough that one can market fiction effectively with it.