Them being sent to an alternate reality by Madara or a mass genjutsu by Madara would make the most sense. If it's the later Sakura is still herself and is aware of the genjutsu because of the ability Kishimoto has shown Sakura has- in part 2 even resistant to Uchiha level genjutsu. (maybe this will be the Sakura arc that Kishimoto promised but may have run out of time to put in the manga) If the story is about Sakura knowing the situation is wrong and she has to make the heartbreaking situation of freeing Naruto from a genjutsu where he has loving parents- whoa... that will be intense. (but right up Kishimoto's alley....)
And to make it even better, Tobi twists around their feelings and screws them so hard so that they fight each other (or at least he tries to). If this scenario is true, I can see Tobi try twisting Naruto's feelings so that Naruto's hate is directed towards Sakura by saying something along the lines that she was the one who took away his deepest wish of having his parents alive and live together with him like a real family. That would be even more sick and twisted than resurrecting his parents as ET's.
But the one problem is, the movies usually sets the plotline around the anime's current plot. If the plot as you say it is, I kinda doubt it. But since Kishi's writing it, we'll have to see.
Interesting. It looks like Naruto's going to Edolas. 
Now that is just win. But on a side note, I don't think everyone knows this, but FT's first movie is going to be released this summer. Not only that, Mashima is also going to be writing the story as well. Confirmed here:
FT's First Movie announcedAnd Oda is also said to be the executive producer for OP's movie this year. If that's true, then this will be very interesting. But OP's movie will be released at the end of the year while FT and Naruto's movie will be released this summer. So the highlight will be FT vs Naruto. It's kind of interesting, because Mashima will be trying to one up these two and show off his skills. It's kind of like a greenhorned kid trying to impress and outdo his senpais.
Post of the day right there. You friend are win.
I think people still believe that I want Sakura to suffer, that I'll get some weird pleasure for it, that is no the case. I'll explain again, seeing turmoil in characters makes us feel more attached to them, doesn't matter which one. I'm not gonna laugh seeing her feel bad, I'm gonna root for her to fix thing the same way I would support Naruto if he was the one with problems.
Besides I'd rather Sakura not go into some full out depression, that's just a downer. Just her missing the old Naruto and wanting everyone to be how they were before. I don't want her to start crying or anything like that.
Exactly. And I'd also like to point out what DK said a while back.
"You never know what you have till it's gone"
It's this saying and lesson that Sakura will learn well. Think about it, WHO, from the previous generation that went through this??
You guessed it.
Tsunade. Tsunade went through this painful lesson with Jiraiya's death, and now it's repeating itself with Sakura. But the only thing is, she'll have a second chance to fix things right. in which she'll surpass Tsunade in that aspect. But of course, it would be a painful decision to make because she'll be taking away his greatest happiness.
But a movie dedicated to Sakura? Don't get me wrong, it would be awesome but how will they get profit from it? Sakura is not as popular as Kakashi, Sasuke, or Naruto. I can't speak for the whole Naruto fandom but I doubt the movie will get as much audience as the other movies if Sakura was the main character. I mean I wouldn't see a Naruto movie if the main character was say, Kiba, Shino, Inari or Tenten. Isn't it the same for most of the non-Sakura fans if Sakura were the main character?
Yeah, that's the thing. She's only somewhere in the top 10. But with her recent developments I suspect a dip in her popularity. I don't think a Sakura-centered movie would be a lucrative option for a plotline.
Lastly, I'd like to give my own two cents on the plot. I believe that Kurama will also play a huge part here if ciardha's theory is true. Think about it, Bijuus can also help their Jinchuurikis break out of genjutsu if they want to. So maybe Kurama will actually work together with Sakura to help break out this Genjutsu of Tobi's. How? Kurama will share his consciousness with Sakura because Tobi's blocking his mental connection with Naruto.
