The only Earth-2 heroes who ceased to exist in the comics' Crisis were those who had exact Earth-1 counterparts -- mainly just Superman, Batman, Robin, Wonder Woman, and Aquaman, as well as associated characters like Lois Lane, Catwoman, Huntress/Helena Wayne, etc. Earth-2 characters who had different identities from their Earth-1 counterparts (like Alan Scott, Jay Garrick, and Carter Hall) or who had no direct equivalents (like Hourman, Sandman, or Doctor Mid-Nite) were folded into Earth-1 history as the generation preceding the modern heroes. This was illustrated in Roy Thomas's All-Star Squadron, set in the 1940s on Earth-2. In a scene set just before the end of the Crisis, there was a group photo in which all the Justice Society members and associated heroes posed together, including Superman, Batman, Robin, and Wonder Woman, but once the history changed and the merged reality settled, Superman, B&R, and WW had been replaced by Uncle Sam and the Freedom Fighters, but everyone else in the group photo was still there.