Hi,
I've studied so many myths and I think I might have something to share about.
From my understanding the to twins and also the Divine couples of divinities as Isis and Osiris i.e. are just metaphors to indicate the hidden nature of the human soul and also point to a realization of a whole human being.
The legends and the stories in which those divinities are involved indicate a process that from duality leads to the One. They describe a mystical path in other words.
The same do alchemical metaphors, and the Androgyne is one of the step of the process. In the Androgyne the "two things" are going to became One thing in a Creative way.
Most of them, most of those myths, just describe in a narrative way, and somehow mysterious and cripted way, how to overcome duality.
Well, there could be a lot to say about, and this is not the right place - since is a supportive site for transgenders and not a forum for mystical speculations.
BTW, I think you had a worthy intuition there: those myths talks about a "change" within the human being, a transformation in order to become more integrate with reality - which is not splitted into two things, but it's One Wholeness.
Just my cent here.
Hugs,
Aly