Jokes aside, I think the correct one should be “binaria” because it’s “persona no-binaria”, where “persona” being a female-gendered word still includes everybody (persono doesn’t even exist).
Native speaker here and no, that wouldn’t be correct as a general rule. The most typical would be talking about or someone else like “yo soy no binario/a” and “yo” would be a he or a she depending on who is saying that. If you’re talking about someone else it’s “el/ella es no binario/a” for example.
Also a native speaker here. You can also just not specify “el/Ella” because the context isn’t relevant. I.e. “es no binaria”. You can also just pluralize the person to get around gendered wording, I.e. “ya llegaron” for “they have arrived” rather than “el/Ella ya llego” for he/she has arrived, but this is informal and may sound odd to someone of a different dialect from me, but I think this should at least be intelligible to Latin american Spanish dialects
The point of being non-binary, though, is that they are neither “he” nor “she”. Hence the post.
