If this situation will appear in copying operations, source file will not be copied. If you were run rename operation, ID3v1 and ID3v2 tags would be updated in this repeated name file.

Other Topics
Can I resize the width of the any column in Mp3 ID3v1v2 Tag Edit & Sort Tool?
What is mp3?
When the progressbar will reset to zero after mp3 tag updating, removing, clearing, restoring, pasting, copying or renaming?
Can I edit mp3 file from QuickTime MOV movie?