If I were a hero, I'd be Martin Luthor (Part1811)...

 Superhero Anydays

Today we have, by George Perez, the cover of the Crisis On Infinite Earths #5, from back in 1985 or 1986.  The cover shows the merging of Earth-1 and Earth-2.

I'm gonna try to name them all...don't know if I can though.   Top to bottom left to right (only the main headshots up front, I'm not trying to see and identify all the little headshots behind the main ones): 

Red Tornado, Scalphunter, Wildfire, Halo, Flash (Earth1 & Earth2), Johnni Thunder, Amazing Man, Cheetah, Soloman Grundy, Dr. Mid-Nite.

Dawnstar, Martian Manhunter, Batman, Firestorm, Superman (Earth1 & Earth2), Pycho-Pirate, Spectre, Johnny Quick, Firebrand, Robotman

Sgt Rock, Dr. Light, Blacks Canary, Lead, Hawkman (Earth1 & Earth2), ?, Star Spangled Star, Fury, Dr. Fate, Ultra Humanite

Nightwing, Blue Devil, Wonder Woman (Earth1  & Earth2) Obsidian, Huntress, Wildcat

Supergirl, Phantom Stranger, Cyborg, The Atom (Earth1 & Earth2), Sandman, Shining Knight, Black Canary, Kong

Swamp Thing, Dr. Polaris, ?, The Joker, Green Lantern (Earth1 & Earth2), nuklon, Tusami, Guardian, Ibis, Tarantule

Chameleon Boy, Solivar, Jonah Hex, Starfire, Green Arrow (Earth1 & Earth2), Robin, Power Girl, Northwind, Thunderbolt, ?

?, Killer Frost, Snapper Carr, Geo Force, ?, Jade, Hourman, Silver Sacrab, Plastic Man, Starman

POLT