Stuff that I’ve seen from people addressing this:

• using -@, -e or -x instead of either.
• picking either randomly, and acknowledging “language limits”. (laypeople way to say “grammatical gender does not necessarily coincide with social gender”)
• picking both and using them randomly
• triggering gender agreement with some additional word, e.g. “la persona no binaria” will always use -a since it agrees with “persona” (person)
• “the dance” aka rephrasing

The -@ and -x things don’t work well when spoken.

Spaniard here, you pretty much nailed it. -x makes no sense as it breaks like every rule about the Spanish language so I’ve never heard it outside of Americans trying to be correct. -@ works, but we pronounce @ as [aˈro.βa] so most would just pronounce it like a normal -a instead. -e seems the best to me but I don’t think I’ve ever seen that one before. Another thing is that most Hispanics don’t think of gender in the same way that Anglos would, as its more ingrained in our language. Of course he have non-binary people here, but its just not as prevalent of an issue because

i’m not a spanish speaker but christ -e just seems so obviously the best choice, it looks normal and seems to fit as well into the language as you can expect a new not 100% organic thing to do.