Since kint precedes the verb, is the focus on kint? (where do you see a woman)?
Does this put the focus on "a woman"? Egy nőt látsz kint
What is the neutral version of "you see a woman outside"?
Yes, "Egy nőt látsz kint" puts the focus on the woman. Neutral version would be "Látsz kint egy nőt".
Since kint is a postposition, who does it go at the front of the sentence? Shouldn't it be "Látsz egy nőt kint" to show that the woman is outside, or "Látsz kint egy nőt" to show that the person seeing is outside?
No, "kint" is not a postposition. It is a word indicating a location: "outside". That is all it is.