Renames files in archive.
rn <archive_name> <src_file_1> <dest_file_1> [ <src_file_2> <dest_file_2> ... ]
7z rn a.7z old.txt new.txt 2.txt folder\2new.txt
renames old.txt to new.txt and 2.txt to folder\2new.txt .
  -i (Include)
  -m (Method)
  -p (Set Password)
  -r (Recurse)
  -stl (Set archive timestamp from the most recently modified file)
  -u (Update)
  -w (Working Dir)
  -x (Exclude)