Put the verb on the button
"Yes" is a bad label when a click can delete something.
I have a minor grudge against confirmation buttons labeled "Yes."
A dialog asks whether I am sure I want to continue, then gives me Yes and No. All the dangerous meaning is hiding inside "continue." It could mean deleting the local copy or replacing the newer file. "Yes," apparently, is meant to cover both.
Put the action on the button: "Delete local copy" or "Replace file." The wording looks harsher because the action is harsher. Softening the label does not make the click safer.
I would rather have one plain sentence than a warning triangle and a small legal brief. "This removes the file from this device. The cloud copy will remain." Now I know which file is at risk. I also appreciate a Cancel button that gets keyboard focus, rather than putting the dangerous choice under an impatient Enter key.
"Are you sure?" tests my confidence. Confidence is rarely the issue. I need to know whether the software and I are talking about the same thing.