I only used AFAC instead of AFAB because it actually was appropriated from intersex people, and science can tell our sex when we're fetuses in the mother's womb!

But human conception when it occurs naturally in a woman's body doesn't take place in the womb. Conception occurs in a Fallopian tube, then the fertilized egg has to travel to the womb and become implanted in the uterine lining.

Moreover, after human conception occurs, several stages of development have to occur before the fertilized egg reaches the stage where it has turned into a fetus. The fetal stage of development doesn't start until 8 weeks after conception.

Also, when conception occurs in the natural way, no one "assigns" the sex. Sex is determined by whether the sperm that fertilizes an egg is X or Y. It's a matter of chance, not an intentional assignment - unless, that is, you believe the sex is decided by a divine being.

Even though intersex are one in five hundred million

What? Your figures are way, way off.

I would date one that is XXY because two x chromosomes= biological female.

No, a Y chromosome or SRY gene usually on the Y = male.

Two X chromosomes is not the only formula that = female. 45, X0 and 47, XXX = female too. There's also a syndrome known as XY female or Swyer's syndrome.

Finally, most DSDs - aka "intersex" conditions - do not involve unusual chromosome patterns like XXY. Most occur in people who have the usual pattern of 46,XX or 46, XY.

My unsolicited advice is that since human conception and what happens afterwards, and DSD conditions, don't seem to be areas you're knowledgable about, best leave them out of the convo altogether. Just say you're a female human exclusively sexually attracted to other female humans - no need to bring conception, embryos, fetuses, DSDs etc into it.