Sure. But they them has been hijacked and I want it back. Everybody now assumes it is some kind of code word for gender mixed or gender confused or gender trans when it just means unknown. I want my language back.
I suggest you use another language for this purpose. Austronesian languages are ungendered, there is no he/she.
In Hawaiian (a language native to the US, note), you just say o’ iya (pronounced “oya” which is close enough) for he or she.
(my wife was learning Hawaiian at one point).
But thats not the most common Austronesian language in the US. That would be Tagalog, with 2,000,000 US speakers, and you would say “siya” for he or she.
So instead of using some weird English make do, when you are dealing with a person of uncertain nature, just say “oya” or “siya”.