At last, the Who's Who in DC Comics is coming in omnibus format on April 13, 2021.
Collects Who's Who: The Definitive Directory of the DC Universe #1-26 (1985), Who's Who Update 1987 #1-5 (1987), Who's Who Update 1988 #1-4 (1988), plus material from Action Comics Annual #2 (1987), Batman Annual #13, Blackhawk Annual #1 (1989), Detective Comics Annual #2 (1988), Dr. Fate Annual #1 (1989), Green Arrow Annual #2, Justice League Annual #3 (1987), Secret Origins Annual #3, Swamp Thing Annual #5, The Flash Annual #3 (1987 series), The New Titans Annual #5 (1995), The Question Annual #2 (1988), and Wonder Woman Annual #2 (1988).
https://www.amazon.com/Whos-Who-Omni...7950599X&psc=1