Going to use this as a fandom-board for the moment, as I'm not in any other fandom communities right now and I don't think my friends would understand my love of My Little Pony and the desire to make weird theories sometimes.
So, assuming anyone here is interested: I've recently watched Equestria Girls, and want to share a bit of a (spoilery) theory.
First off, I gotta say that I didn't have high hopes for this movie, but ended up enjoying it! The music made me want to put a pencil through my ear--I'm not really sure why, I like the series music, but this was just... different--but the writing and dialogue was on-level with the series (within the constraints of the premise--we can't have our HS AU if Sunset or Twilight just steals the damn crown out of the office, of course horse ears/tails are trendy fashion accessories, of course anyone everyone gives a crap about school spirit... eesh), the idea of a literal high-school AU universe amuses me, and fish-out-of-water Twilight is always fun. Plot holes abound, and I had trouble getting into everything being translated into HS-level bull, but... it was fun.
So anyway. We know that Equestria Girls continuity has a Twilight Sparkle--Pinkie Pie recognized her and her little dog. But she doesn't go to this school. And she really COULDN'T--Sunset Shimmer's tactics for separating the five friends wouldn't have worked with an alt-Twilight to pull them together! She's performed exactly this function in a couple of episodes, if I recall.
Obviously Sunset Shimmer would know this--for the very same reason she knows about the Elements of Harmony at all. Magic, or friendship, is what ties it all together.
We also know that Sunset Shimmer doesn't shy away from the harsher tactics--she took over the entire population of Canterlot High as zombies to violently dominate Equestria, for heck's sake!
I think that Sunset Shimmer killed the Equestria Girls-universe Twilight Sparkle, and since she's living in a high-school AU (and self-aware), she covered it up by making it seem as though Twilight had transferred to a different school "in the city." Or--pony!Twilight moved to Ponyville from Canterlot. If Sunset Shimmer could get human!Twilight during her corresponding move...
Other possibility is that Twilight just never moved to Canterlot High in this universe. But... the idea of murder is sufficiently plausible to me that I'm having trouble discounting it.
(EDIT: Bill says that maybe, in the underhanded way she does things, Sunset Shimmer engineered the need for Twilight Sparkle to move to the city. Sexting scandal? Probably not. But ... yeah, he's got a point, if there's a way to cause enough High School drama to necessitate a transfer of schools (and there is!), Sunset Shimmer is capable of it.)
(So yeah. We can accomplish this without murder.)
So, thoughts?
Oh! Also. I was pleasantly surprised by the movie. You know what I'm NOT pleasantly surprised by? The toys. Seriously, I imagine a desire to sell Monster High or Bratz-type dolls is the entire reason they caused the series to be made (you definitely see the writers chafing against the premise at a point or two), so... why do the dolls SUCK SO MUCH? The girls have unique personalities, and not a one of them involves looking sultry through half-lidded eyes at the viewer! (OK, I can see Rarity doing it while being dramatic, but...) The dolls don't even maintain any sort of independent visual identity!
Just... ugh.