I'd call the person by whatever pronouns I think they are by looking at them. If I can't tell I'll ask. If they say something that's not part of the English language I'll stop conversing because at that point I've realized they're too crazy to talk to.
English
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Apparently thinking you were born the wrong way isn't crazy enough.
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But thinking you are an asexual binary wolf isn't normal. That's -blam!-ing weird, and a dream