Could we have a flashback episode in the future? Not just a remake of an old episode, but something someone is telling that gets turned into an episode (similar to what happened in Training Daze, which Jessie, James and Meowth).
I started thinking this due to the banned Rocket vs Plasma episodes. Team Plasma are appearing now. I suppose we will have some backstory regarding the organization as a whole, but how will they handle that two-parter? Will they simply ignore it and have something with elements from it, or will we be told what happened there with Team Rocket, Team Plasma and Jenny, Looker and Juniper? If that were to happen, I suppose we would have something which we may call "a flashback episode" - the main focus of the episode(s) being the events depicted during the flashback.
But then I started to think: could this be done with other things? For example, imagine an episode which starts with Ash telling Cilan/Iris that he once saw/done this/that and when he starts telling it we are carried to a flashback episode with everything that is told appearing - picture it! - Ash, Brock and Misty, along with their Pokémon and Team Rocket with their old motto and Pokémon all as they were during Johto/Kanto/Orange Islands doing something (the same something that is being told by Ash to Cilan and Iris), all with the old music and with elements from the past, but everything done as it is now (regarding the animation, the fact that it is all 16:9 and HD, etc). I think it would be nice (and unlikely, I guess, though it could be some sort of special episode).
What do you think? (And this is not regarding the appearance of Misty, this could be done with "recent" characters such as Dawn or Paul)