My knowledge is by no means complete, but here’s what I have right now (I’m sure I’ll think of more, and regularly update this)
Acero (Spoiler: Suicide Squad Seven)
Alice Oh (Spoiler: Poison Ivy: Thorns)
Apollo (God of Olympus)*
Apollo (God of Rome)*
Artemis of Bana-Mighdall
Batman (Bruce Wayne)**
Batman (Bruce Wayne, Jr.)**
Batwoman (Carrie Kelley)**
Batwoman (Kate Kane)
Batwoman (Ryan Wilder) (Spoiler: Batwoman Season 2)
Bernice Yoon Milonas
Cheetah (Barbara Minerva)
Comet (Andrea Martinez/Andy Jones)
Danny the Street
Green Lantern (Alan Scott)
Green Lantern (Jo Mullein) (Spoiler: Far Sector)
Huntress (Helena Wayne)**
Katie (Spoiler: Crush & Lobo)
Kid Quick (Spoiler: DC’s Very Merry Multiverse)
Mandy Anders (Spoiler: I am Not Starfire)
Nyssa al Guhl
Question (Renee Montoya)
Quick Draw McGraw
Rag Doll (Peter Merkel, Jr.)
Ray (Raymond Terrill)
Red Robin (Tim Drake)**********
Robin (Brutarch Wayne’s girlfriend)**
Robin (Damian Wayne)**
Robin (John Grayson)**
Robin (Maps Mizoguchi)** (Spoiler: Batman Black and White)
Robin (Matt McGinnis)**
Robin (Thomas Wayne)**
Robin (Tris Plover)**
Rorschach (Walter Kovacs)
Shazam! (Billy Batson)**
Steel (Natasha Irons)
Superboy (Conner Kent)**********
Syl (Spoiler: DC Pride)
Syszn of the Cliffs (Spoiler: Far Sector)
Thunder (Anissa Pierce)
White Canary (Sara Lance)
Wink************* (Spoiler: DC Pride)
Wonder Girl (Cassie Sandsmark)*
Wonder Woman (Diana of Themyscira)
Wonder Woman (Mala)
*I could be wrong, but it’s been my understanding that all the Gods of Olympus are pansexual.
**VOTING CLOSED! Your Complete Guide to DC's 2021 Round Robin Brackets - #76 by HubCityQuestion And unless he says it himself, I refuse to believe he meant anything other than EVERY Robin.
***No DC publication ever referenced this character being queer or genderqueer, but in material from the original publisher, either they or an alternate version are shown to be queer and/or genderqueer.
****Deathstroke is not canonically queer, but Marvel’s pastiche of him, Deadpool, who has, by any metric, surpassed Deathstroke in popularity, is pansexual, and the antimatter doppelganger of Deathstroke was, in turn, based on Deadpool.
*****The new Fadeaway was revealed in the one-page preview of Blue Beetle: Graduation Day, which lost, so we will never know their true identity.
******I generally assume male characters played by cis female actors (and vice versa) are trans. And given his age, it could explain his voice change between Hands of Time and Sons of Garmadon: He might’ve just become old enough to start taking hormones (although I don’t know what the laws are for someone who’s drank Tomorrow’s Tea). That’s just me, though.
*******Not really a “character”, but Berlanti appears as himself in the end credits of many of his productions, including some in the Arrowverse.
********Pride Profile: Shrinking Violet and Lightning Lass
*********DC has never depicted Loki as such, but in Norse mythology and many modern adaptations, Loki has been shown to be genderfluid.
**********I can’t seem to find the article DC published about it a couple years ago, but it’s generally accepted that Tim Drake and Conner Kent are in love with each other.
***********Pride Profile: Starfire
************Not clear how this character fits into the LGBTQ category, but they were a part of the JLQ. (Spoiler: DC Pride)
Alright, that took, like, half an hour. And I’m sure I’m not done.