Current Kakashi lacks the Sharingan, and would get slaughtered.
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You might want to be careful about starting threads about characters you aren't up to date
I think Itachi could win in most timeframes, though when Kakashi got really good at Kamui he may be able to pull out some wins but Itachi is still really really dangerous. If he had Naruto lent chakra, then he'd win.
And then, of course, after his final upgrade, the results are obvious...
You should have specified the arc you were using for Kakashi (Part 1/Gaara Retrieval/Invasion of Pain/Hokage Summit/etc.). Any version of Kakashi prior to the one seen 4th World War would lose more often than not to Itachi. Assuming full strength for both of course.
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