First of all this is where this idea comes from.

OK Think of it this way, in this series High school Foot ball players are standing in for King Author and his Knights.

My twist on this idea; (This under the assumption Twilight can die)

Equestria in the future, a group of mares are brought into the past, when the show takes place, and have to assume the role of Princess Twilight and her Counsel of Friendship

An interesting twist, but you're going to have to explain how that is possible and come up with some way all their stand-ins can be mistaken for the Mane 6.

5387111 Well may be for the first part Stare Swirl the bearded, because he usually caused problems like that.
but as for your second, I have to think some more.

Ooh Double the irony if it is Sunset and the Equestria Girls... LOL

5387067

If it is an "Equestria of the Future," that the new heroes come from, then it implies OCs taking the place of the six, albeit temporarily, and that will take some good writing to pull off.

Knights of Justice seems to have made it work by making the Leader and the Lancer into future analogues for King Arthur and Lancelot by making them Arthur King and Lance, respectively. The artist Mauroz is doing a Sailor Moon styled crossover comic that does something similar with Twilight and her friends.

Using this method could give you a "Future Twilight," possibly a descendant of Twilight Sparkle or Flurry Heart, and then at least one other descendant of a Mane Six character (or recognizable supporting character) for her second in command, while the rest could be anyone, really, as long as they have personalities.

One of the general conflicts of a "next generation" storyline tends to be the protagonist trying to embody certain aspects of their ancestor while still trying to make their own name for themselves...

5387111 of course there is always Discord.

5388253 Well I have a lot of other projects that come first but I would like to try this I am still working on all the concepts, Flurry Heart standing in for Auntie didn't think about that. Some one suggested I use all the existing Au to pull Main six from there.
But like I said I'm still working on it.
Thanks for your input.