1.x) Which one will be you? 2.x) Which one will you be? Since the OP's two examples only had a single verb in them ("is" vs "are"), then as to what the subject is will, in this case, depend on the verb that is used -- for the speaker/writer will have used subject-verb agreement between the subject and verb. So, the answer is: Both are "correct".

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One-to-one is used when you talk about transfer or communications. You may use one-to-one when you can identify a source and a destination. For eg., a one-to-one email is one sent from a single person to another, i.e., no ccs or bccs. In maths, a one-to-one mapping maps one element of a set to a unique element in a target set. One-on-one is the correct adjective in your example. See Free ...

Which one is grammatically correct or better? I have two assignments, One of them is done. I have two assignments, One of which is done. I watched a video tutorial that the teacher said the ...

pronouns - "One of them" vs. "One of which" - English Language Learners ...

"Which one is the best" is obviously a question format, so it makes sense that " which one the best is " should be the correct form. This is very good instinct, and you could even argue that the grammar is good, but at best it's unnatural.