"Hey cunt" works for anybody. But your mileage may vary depending on your location.

M'theydy

Slightly off topic but I really like the approach where the honorific is just dropped entirely. So just [Name]. No Mr/Ms/Mrs. It mostly doesn't serve any purpose anyway.

I have started just using M. Like, "Dear M. Lastname". I saw it being done in French and just adopted it for English too. No one's complained yet. (Have also seen Mx. but figure that could be confusing.)

I vote that we change it to Mmm.

That will make all honorific communications sultry and interesting.

Mmm Adulated, We appreciate your interest in our organization, but we regret to inform you that we will not be able to hire you for the role. Please continue to.....

Mf

Too bad we can’t adopt the Japanese “-san” honorific, as it is gender neutral!

Not a contemporary one, but during the French Revolution, they used 'Citizen' for everyone.

Mx. seems the most commonly used for gender neutral. It's used both by non-binary people and in cases where you purposefully don't want to put a gender as a prefix.

Homie

Sup, fool?

Seconding the honorific "Mx". From what I've seen, it's decently well-adopted in the non-binary community. I've not seen it much used outside of that community--it seems to be used mostly when someone 'needs' an honorific but doesn't fit into the 1950s list. I've heard it pronounced "Mix" and "Mux". I tend to go with "Mix".

IRL, I've used "Hey, you" and "Yo!" when hollering at folks I don't know (example, "Yo! You dropped something!")

Sidenote: As a nonbinary person, I prefer not being given an honorific over being given the wrong one.

Minirant not directed at OP: And omg, if you need to go with a feminine honorific and you don't know whether the person is married, go with Ms, not Mrs. or Miss. The connotations of the wrong one are just creepy.
Not married and called Mrs="Hey, you're too old to be unmarried. Please feel judged about your relationship status"
Married and called Miss="Hey, you're too young to be married. Please feel like I don't respect you as an adult."
In all cases Ms="I don't know and/or care about your marital status and I'm trying to be polite"

"My Liege"

“Yo.”

Lord [name], my [name], my dear [name], the one they call [name], oh great and powerful [name].

Jokes aside, one I've heard of that I liked was "misc" like miscellaneous lol. That one works a bit better in writing that verbal though.

Some other popular ones include Mx, M, Ind/Div, N/A, Mt, Nb, and many others.

For my own personal suggestion, I kinda like the idea of using "The" as a gender neutral title. Like instead of Mr or Ms Smith, it's The Smith. Has a nice ring to it lol

Mx is common-ish among nonbinary people. Here’s a relevant poll regarding people’s usages of it: https://www.gendercensus.com/results/2023-mx/

Comrade, or Captain

Mx (pronounced "mix") is getting more common

Also, Dr

My wife and I are both Dr. X

Comrade

I vote stop using honorifics entirely

"Hey, you!"

"Bro"

"Oi, fuckface!"

'Citizen...'