Let's take this in two situations.
You see someone on the street. You HATE them because of their physical attributes. Not very likely. But you have seen them, "met" them, if you will, and it's highly unlikely that you'll develop an automatic loathing for them.
You meet someone online, or on the phone. You talk to them for a while, but you haven't "met" them physically. Or in person. But you know their personality based on what they say/type. Much more likely that you develop a strong dislike this way.
But it's not possible to hate someone you don't know. Because you don't know anything about them, except maybe physical appearance.
Maybe you should rephrase your question to "Can you hate someone you haven't
met?"
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