Early 1990s Mark Waid introduces the idea that the heroes remember the crisis but as it happened in the merged universe which was about an invasion from the anti-matter universe not a multiverse. Later Johns takes it back to the original concept.
It got really tricky for me because there may be things that either weren't addressed or I never read. At this risk of going slightly off topic, let's take Superman.
Everyone in his life completely changed. Krypton completely changed. I don't know how many major characters had so many differences and everyone he knew, including Luthor, changed.
The post-Crisis Superman was never Superboy, and all those adventures never happened. He was nowhere near as powerful as Earth 1 Superman as well. Supergirl never existed.
But when Superman emerged from Crisis, he WAS still Earth 1 Superman. He buried Supergirl. And they all remembered.
So something must have changed.
And what about Barry. Why did they remember him but not Supergirl?
If there was a post-Crisis Crisis, then who played the role of Supergirl?
Why did Barry stay dead on the reset? Kind of why did Oliver also stay dead?
I know today in Convergence, the events of COIE were completely wiped out and with the help of heroes of other Earths, the original multiverse was restored.
That's sadly something DC hasn't followed up on.
But there are so many questions. I am hoping that the CW version changed things as well, especially for Superman, and by the time Superman premieres, a similar effect will happen.
It would even be interesting if they addressed this issue on one of the shows.
I doubt the characters in the shows will forget the pre-crisis worlds, they're probably going to want to be able to continue to use their histories from before.
That's an interesting issue. Is that better or worse? They have an opportunity to jettison continuity in continuity.
Yup, the Paragons all remembered, and J'onn went around mind-melding the memories back into the other heroes' heads (with a total lack of regard for consent, by the way).
In fairness, it's hard to give consent when you can't make an educated decision, though this was a weak plot point. How could Jonn restore memories to events that never happened from the perspective of the non-paragons? These weren't hidden or suppressed memories like with Alex last year. Could Jonn give his memories to the others? Sure, and to that extent, he could educate them, but it makes no sense that Jonn could restore the ACTUAL memories.