The gender can be guessed from the username. From what I know, in Japan there's an archetype in Animés and Mangas of rich spoilt girls addressed by their butlers and servants as -Sama. It's an honorary titles thing that the japanese go by... -kun, -chan etc. Any animé viewer can perhaps recall the use of "Ojii-sama" which is like an equivalent of "mistress" "miss" or "princess". So we can use this theory to assume Zone-Sama is a girl? It's possible, personally knowing females with fascinations with this kinda content.
If you look at the way she presents herself, you can compare her to a Japanese mangaka, I mean, she has a mascot, a -tan (that creepy little girl is known as Zone-tan and lol, believe it or not but officially her name is "unknown" XD), which is a anthropological representation of what she does (look up the "OS-tans which are anthropomorphisms of operating systems as a example of what Im talking about).
Concerning the nature of her (or as rockyoutothecore thinks, their) works, it can be very comparable to the likes of doujinshi you find in Japan, just as many people have said, parodies of popular copyrighted material. Zone-Sama is perhaps filling in a very niche market of these doujinshi type things for the western side of things; because of course there's plenty of the stuff based on Japanese cartoons etc, but hardly any from western shores. And I say this 'cos there's an obvious anime overall influence on her works, so it wouldnt be so far fetched if she works in a similar fashion to Japanese artists.
Personally I reckon it's a solo effort for the most part of her work, they don't come out regularly enough to be contested that it's a team who are animating, perhaps at most a duo? I did notice she's collaborated with two other animators from the web: "Buttercupsaiyan" and "Pleasure Bon Bon" (I don't know much about these two though but I assume they're in association with the same commissioner Hentai Key)
I see a lot of discontent with the existence of these parodies, but you know, if you don't like them don't watch them; and it's meant to be funny I reckon, parodies are meant to make you laugh, shits n giggles the joke's meant to be an "OMG what are they doing to my "childhood" cartoons!?" It's like Zone-Sama's motto "Raping your childhood since 2000", keep it light hearted :). If you feel the need to preach that it is wrong/immoral, your energies are better spent else where, to be honest - people on the internet can be pretty resilient when trying to sway their opinions.
Whatever your opinion of Zone-Sama, what we would most definitely agree on is that the quality of animation and art imitation is superb to say the least and in some cases kinda hilarious how well voice samples are strung together to make a cohesive conversation between the characters. Truely an artist's handy work.
Ah, and to answer rockyoutothecore, if you want to find these works, you know the internet is abound with soloutions depending how hard you look for 'em ;) I feel the hentaikey subscription may be money on the side, and perhaps for people who wouldn't know how to get a hold of the animations otherwise lol. Nice way to keep a low profile perhaps too... Jab Comix is also another interesting illustrator, and I feel his works are waaaaay more uncomfortable to view compared to Zone-sama's stuff.
On a side note, I'm wondering if anyone knows about her works that aren't affiliated with Hentai Key. Or if indeed she has any work that isn't of a hentai nature.
[ah ha ha... apologies if this seems like a lengthy lecture XD but I hope I've enlightened and not offended or caused an annoyance :) funny what sorta of thing I make my very first post on Newgrounds is about XD ]