@621Chopsuey  

 
I presume you don’t count the comics, because if those are accounted for there’s more than two world, and the Mirror Universe seems to be structured in such a way that we can assume it would contain (or at least have formerly contained) a Mirror Sunset (likely a once-noble individual who recently had a tragic fall from grace which left her desperate and dangerous).

@621Chopsuey  
Something along those lines, combined with the Prime Sunset/Peter crossed over to the other side and lived there, essentially being some kind of link between the two worlds. I won’t get more specific then that for Peter since your still catching up, but essentially they not only have the same prerequisites, they also fulfilled a nigh identical role.
 
(shrug) Alternate dimensions are inherently weird. Anyone who existed in the past 15-50 years existed in the other dimension at that time as well, even if it was a very different life. The fact that they share or shared the same people is part of what makes 2 out of infinite possible dimensions, alternates. But after a certain point, the differing Quantum paths can start to take lives in one world but not in another.
 
Heh, although that last paragraph of mine was mostly just observation and techno-babble, I think its at least somewhat accurate.

H-Sunset: Who are you?  
Sunset: You.  
H-Sunset: Me?  
Sunset: Who?  
H-Sunset: [screams, faints]
 
 
@CronoM  
So you’re saying (and forgive me, I’m catching up with Fringe) H-Sunset died of an incurable disease or died in a car accident, leaving the prime Sunset the only one in existence. That would make a hell of a lot of sense to H-Sunset’s absence.

@Background Pony #A187  
A take on Too Many Cooks.

@SentryBronyPlatinum  
What the heck is that from?

Sunsets: “You have got to be kidding me…”
 
Also,  
Human Sunset <3

Pony!Eq Sunset Shimmer: “Who the Tartarus are you?”  
Human!Eq Sunset Shimmer: “Who the Heck are you?”  
Pony!Eq S.S.: “You talking to me?”  
Human!Eq S.S.: “You talking to me?”  
Pony!Eq S.S.: “It’s like talking to a mirror.”  
Human!Eq S.S.: “I don’t see a reflection more alive than my own.”
 
 
Darn those twintails on the other Sunset Shimmer.

@Background Pony #BD85  
THERE CAN BE ONLY ONE!!!

@Background Pony #BD85  
I know, there’s still three fuckers left for me to find… and when I do…

@Larg  
Possible, but not necessarily if Sunset was part of a weird fate thing that had her link the worlds and become the human Sunset.
 
Sunset’s been on the human side for a full 30 moon cycle. Its very possible the dimensions recognizes her as both the pony sunset and the human sunset.  
Its the only reason I can think of to why Sunset’s magic specifically linked the worlds for good.

@Larg  
There is old saying: “There is at least six doubles of you walking in the world”.

@Larg  
I’m only assuming Original Human!Sunset would be displeased of this situation.

@FanOfMostEverything  
Not accoring to original Human!Sunset…
 
If a copy of me were running around using my identity, even if it’s me from another dimension, I would demand an explanation.

@CronoM  
I see, I see…
 
However in order for Sunset to link BOTH worlds would mean that the human world EXISTS beforehand, so it’s only logical to assume that somewhere in human world there IS an original Human!Sunset…
 
what do you all think?

@Larg  
If it is identity theft, the government must be really slow because these 2 Sunset Shimmer’s have been in the system for 3 YEARS.
 
Although I have to say the odds of Sunset Shimmer actually having a counterpart is rather low considering she fulfilled some weird fate/cross-dimensional time flux that ensured that 15 year old Sunset would be as old as the ~18 year old Mane 6 in 10 Equestrian years.
 
Sunset’s magic linked the two worlds, so basically she’s the Peter Bishop of Equestria and Earth

I just hope they address that

@Larg  
Is it still identity theft if they share the identity?

Pony!Sunset: Okay me…this is where it gets complicated.
 
(Cue Doctor Who theme…)

Whoa, Whoa, Whoa!!!…
 
Then technically, wouldn’t Sunset Shimmer be commiting Identity theft????
 
That’s jailtime right there.

Why is all of this pony-meets-human-counterpart art popping up all of a sudden? :D

Who know how we think Dr. Sparks is evil? I imagine the opposite effect for Human Sunset Shimmer. Hear me out, since there isn’t a way for her to be an alicorn (i.e. a demigod) I don’t see a reason to be like the old Sunset Shimmer after all Princess Celestia said that she BECAME cruel and dishonest.

@SentryBronyPlatinum  
ROFL

Pony Sunset: “And of course this happens in front of the one mirror in town that reflects my true form. Why do I even walk by this coffee shop anymore?”

But what does it meme?