When there is confusion, we must seek the safest option. That is core to Islam.
When there is a genuine confusion about a person, being male or female, then we must seek the safest option for women in their interaction with that person. Furthermore, we seek the safest option for that person in their interaction with men.
For instance, if this person where to attend a congregational prayer in a mosque where men and women share the same open space, like in the case of the Umayyad Mosque in Damascus, then this person would be in a row between the rows of men and the rows of women, but they would cover like a woman.
In a traditional mosque the rows of men are in front, and the rows of women are at the back, but they share the same open space. Front and back are part of the same body.
Why is there sometimes a confusion about who is male and who is female?
Many things are clear as day and night. However, sometimes there are shades in between.
Referring to cell biology, a human being has two sets of DNA. One is in the cells’ nucleus and the other one is in the mitochondria. The DNA in a nucleus, is a macromolecule coiled and arranged in such a way to occupy a very small space. If the DNA from one human cell were to be stretched and joined with the rest of the DNA from other cells, it would reach from this earth to the moon. Exalted is its maker: Allah.
In human beings, the DNA in a nucleus, contains a repetition of four bases (chemical structures): Adenine, Thymine, Guanine and Cytosine. Adenine pairs with Thymine, and Guanine pairs with Cytosine.
In a male human being’s DNA there are 3060 million base pairs. Whereas a female human being, has 103 million more base pairs than a male. Less and more complete each other.
This is the norm. However, like in many things, there are exceptions and rare conditions:
1. Males, with XX chromosome i.e. with 3163 million base pairs.
2. Females, with XY chromosome i.e. with 3060 million base pairs.
3. Males, with XXY chromosome i.e. with 3316 million base pairs.
This information is now accessible using current technology. However, there is a lot in a human cell that remains unknown and inaccessible. It contains more than intelligence. It contains wisdom that unfolds with time.

“So, take what I have given you and be among the grateful.”
Quran 7:144

The human body is very little known and even less his non-physical side, his spirit.
It would be misleading and fuelling corruption to bring “human desire” into this delicate and complex matters.
Truth is above what one desires.
“It’s my body and I can do with it whatever I want!”, some say.
Really?
“Did you make it?” Liar! You didn’t!
“Did you buy it?” Liar! You didn’t!
“Do you run it!?” Liar! You don’t!
You have been trusted with this body and you can barely keep it clean and safe from harm!
Desire for falsehood is the craving and the longing of the warmongers and the corrupt.

“But if the Truth had followed their desires, the heavens and the earth and whoever is in them would have been ruined.”
Quran 23:71