I have repeatedly told people that I have this list on my English blog and have repeatedly been reminded that I don't (I wrote it in Hungarian). So, this is a post that should have been created a long time ago. Sorry for the wait.
This is a far-from-complete list of traditional stories that I have encountered that have something to do with sex (as in, someone's biological), gender, sexuality, and shifts in all of those. While many people think these are "modern" topics, they are not. It is a selection of stories I have encountered, and because I think it is important to note that they exist, and even more important to examine them, talk about them, and tell them in context, I wanted to make this list available to the general public.
(*Note: All of these stories have their own take on things. They are good starting point for discussion, but I suggest giving them a lot of thought and craft before performance. Talk about them, and talk to many people. Ask for opinions, listen, make changes as you see fit.)
Okay, so maybe this one is pushing the definition of "traditional story" because we only know it from a literary source - Plato's Symposium. But it is nevertheless a famous example from the ancient world, re-told, among others, in Hedwig and the Angry Inch as The Origin of Love, and in Xena the Warrior Princess in the infamous Hercules crossover (which is the first time I heard it). The story essentially presents the origin of "soul mates" of three types: Men who seek men, women who seek women, and men/women who seek the other sex.
A famous beauty for whom two gods, Apollo and Zephyrus competed. When the boy chose Apollo, Zephyrus killed him out of jealousy, and Apollo created a fragrant and colorful flower for his memory.
The angel page
This is a story I found in Legends of the Rhine; it belongs to the city of Elberfeld. While it is not explicitly a love story between the young knight and his page / squire, it lends itself easily to that reading. In the end, the page turns out to be an angel, and after any adventures he sacrifices his life on earth to save the knight's dying wife. It is a touching story in any way.
(**Note: English does not really lend itself to gender-neutral writing. Excuse my mixed pronouns.)
A story from Ovid's Metamorphoses (Book 9.666-797) in which a girl is raised as a boy to deceive her strict father. She falls in love with and gets engaged by her father to a girl who loves her back, thinking that she is a boy. The day before the wedding Iphis prays to the goddess Isis to grant her a wish for change, and the goddess turns her into a man, after which he happily marries the girl he loves.
The princess that turned into a man
This one is a Hungarian folktale; I have the short translation if anyone needs it. It is about a king that only has daughters, and when he has to send his army to war his youngest volunteers saying "men's clothes have always fit me better anyway." On the way she helps out an old woman who sees her for who she is, and helps her with her mission. She falls in love with the daughter of their ally, and gets married, but is afraid to reveal herself to her wife, and therefore the king thinks she is cheating and plans to have her killed. She is sent on a dangerous mission during with, among many adventures, she and her entire crew come under a spell that makes them switch sexes. Our hero is more than happy with the "curse" and returns home immediately to finally admit his full affection for his wife. Explicit folktale bonking ensues.
Another Greek classic. Remember the old blind prophet from the Odyssey? Well, according to legend, he spent seven years as a woman, in some versions of the story as a sacred prostitute in Corinth, while according to others as a wife and a mother. After seven years the spell got reversed, and Tiresias was a man again. This ties into him being blind: Apparently Hera blinded him after he was called on to decide a debate between Zeus and her about who enjoys sex more, men or women (wouldn't we all want to know). Tiresias said women enjoy sex TEN times more (suspiciously accurate number), and was blinded by the goddess and given the gift of prophecy by Zeus as a consolation prize.
The princess and the demon
This one is another favorite of mine, from India. Starts out similarly then Iphis, except in this version the prince(ss) meets a tree spirit/demon on the way to the wedding, and agrees to exchange sexes with him for a year. At the end of the year he returns to the site of the deal, and finds the tree spirit happily married and pregnant. They both agree they like their new sex better, and stay that way.
The warrior girl
I have blogged about this one earlier. It is a Spanish take on the Mulan story, and a prince that can't take "none of your business" for an answer.
The princess who became a man
I heard this story at the Mysteries of Europe storytelling conference in Spain, from Heidi Dahlsveen, a Norwegian storyteller. It is a Norwegian folktale about a princess whom her father wants to marry, so she runs away from home. Later she cuts off her breasts and dresses as a man, and works in a king's court until the princess falls in love with the mysterious soldier and they get married. The princess find out on the wedding night the story of her husband, and she is okay with it. But someone else, listening in (not cool) tells the king, and the king decides to order all the soldiers to undress and find out the truth. With the help of a magical old man, the young soldier avoids humiliation. He goes on to have a baby with the princess, whom the magical old man uses to illustrate a point about letting go of the pains of the past.
Another story from Ovid's Metamorphoses. It is a Greek myth about a girl that is "ravaged" by Poseidon, who then offers to reward her with a wish (how generous) (Poseidon's a dick). Caenis asks to be turned into a man so she can never feel helpless again. This story speaks more to gender difference and sexism, but it is interesting to note that Caeneus then goes on to be a hero among the Greeks and the father of an Argonaut.
That's it for now.
For a very useful interactive map of cultures that have more than two genders, click here.