Identifying bodies in a big crash will be fun.
I guess the preliminary identification, at least, would be male or female, because recovery crews would be using the outdated “gender assigned at birth” criteria. The confusion would come later, in matching up a set of parts with a non-binary ID. The good news is that non-binaries amount to 0.1% of the population, so unless a plane crashes on the way to or from a non-binary convention or something, there will never be many on board at once.