well, since you asked!!! I wanted to draw these out but I'm currently going through artblock. I did a post a while ago about my queer headcanons, but they've changed since!
keep in mind, while these are my main headcanons for these characters, I don't necessarily follow them. for instances, I could say that clark is bi and then in another post I say he's gay- I simply like to experiment! that's the fun with fiction, really. :)
when applying queer headcanons, I try to avoid characters who are already using an existing label in canon (e.g. tim drake being confirmed to be bisexual, coagula being a trans woman). I don't want to promote erasure. but! I have no issue when they're straight and/or cis. it's similar to making a white character black, or any other marginalized communities (if handled with care).
clark | arospec - bisexual
(definitions: under the aromantic spectrum, in relation to having little to no romantic attraction - attraction to more than one gender)
clark struggles with romance. in his head, he has it all planned out and perfected, setting up expectations for himself. but in the end, it doesn't go his way and someone always ends up disappointed or heartbroken. he felt alien in more ways than one.
he's lucky to find lois lane, someone who supports him despite not fully understanding what he is. he appreciates her as a best friend who he wants to spend the rest of his life with.
thoughts
many people think superman is a very sappy, very romantic man in this fandom (it makes sense) but I find the opposite very interesting to explore. as a metaphor, clark kent, being an alien from outer space and adopted into a very human family, feeling out of touch with the people of earth is similar to the experiences of many aromantic people, especially when they grew up in environments that push romance as the norm and something that all people should have to go through at some point in life. they know what it's like to "feel wrong".
bruce | transgender (f -> m) - bisexual - aceflux
(definitions: transitioned from their assigned gender at birth - attraction to more than one gender - sexual attraction fluctuates between none, some, and strong)
as a young child, bruce prided himself as being different from other girls. he was, as they call it, a "tomboy" and he wasn't ashamed of it. his parents never took it that seriously and thought he'd grow out of it. when they were murdered, many things changed for him—including a few realizations about himself. he told alfred about how he felt and the butler was initially in denial about it. but as time passed, he came to terms with bruce's identity like how he came to terms with the dawn of batman. bruce got surgery and changed his name. he is a man, and that's all there is to it. sometimes, he wonders how his parents would react to not having a daughter anymore.
thoughts
there's just something so inspiring about someone as strong as batman being trans. I also think that he and zatanna (who I also headcanon as trans) bonded over their shared experience with their gender identity. in regards to him being aceflux, I think he's more concerned about romance than sex, but there will be times he desires the latter more.
hal | omnisexual
(definition: attraction to all sexes/gender)
hal thought of himself as a straight man at some point. he liked playing around with women, going on dates with them. hell, he loved carol. since joining the caped scene, however, hal opened himself to more options. he admired his teammates, all of which were diverse in everything including gender. hal finds himself enjoying messing around with anyone; men, women, everything in between and out of the binary.
thoughts
I keep tossing back and forth between hal being this and pansexual- the two identities tend to overlap, as anything does with multisexuality (people attracted to more than one gender). the thing that differentiates pansexuality and omnisexuality is that the former tends to disregard gender in their attraction, whilst the latter lets gender play a part in their attraction, thus they have more preferences. I think omnisexuality fits hal more, but pansexual hal jordan is just as valid.
barry | bisexual
(definition: attraction to more than one gender)
barry is attracted to men. well, sometimes. he's attracted to women more and often imagines himself in a relationship with a woman than with a man. but men aren't exactly off the table, you know?
thoughts
what more can I say. sometimes there's just a vibe.
diana | unlabeled - pomosexual
(definitions: no use of gender/sexuality label - refusing/not fitting any sexual orientation label)
when she first stepped foot into man's world, she was prepared for culture shock. she was not prepared for the abundance of terminology that this side of the world has to offer. back in themyscira, they didn't have labels- or at least, not like the ones in man's world. everyone had their preferences. of course, most of her sisters love other women. others, men, even a few... creatures. the rest were celibate for the gods. she didn't know this was such a big deal in man's world, much less a controversial topic. many people asked her what she was, and she always struggled to answer, going with whatever they name her. diana thinks labels like these are wonderful, given that they help many people find themselves, but she cannot use them. diana can love anyone as long as they're capable of being kind. but she does not wish to put a name to her type of attraction.
thoughts
this headcanon sprouted from the discourse around wonder woman's sexuality. I want diana to represent queer people who struggle to fit in the lgbtq+ community, who struggle to put themselves into a category. not having a label leaves a door open to opportunities, no expectations from society. It's not like your sexuality is anyone's business, anyway. do whatever you want!
j'onn | unlabeled
(definition: no use of gender/sexuality label)
j'onn is capable of being attracted to anyone. but like diana, j'onn is indifferent to humanity's labels and prefers not to use any of them. things were different back on mars, and while he embraced earth as his new home, some of her customs are left disregarded by j'onn. on occasion, he'd humor his friends by using the terminology they're familiar with, although he never stuck with it. truly, j'onn did not care about what people name him. he has other things on his mind.
thoughts
I had to think pretty hard about this one. I've always struggled with characterizing j'onn, but I think him being unlabeled makes a lot of sense.
arthur | bisexual - polyamorous
(definitions: attraction to more than one gender - can be or in romantic/sexual relationships with more than one individual)
atlanteans were not much for monogamy. in fact, polyamory is considered a normal model of relationship among arthur's people. the atlantean people love and care for one another. arthur and mera are no different—when they're not busy with royal duties, they go out and about with the locals, taking every chance they get to bond with their kingdom. arthur's affections extends to his friends on the surface, and while some may find it strange, arthur knows he is happier than they'll ever be.
thoughts
poly atlanteans have been a long-lasting headcanon of mine. I've also been considering arthur as intersex!
yes, I do have them for half of the justice league. yes, I do headcanon some of them as straight. it's funny.