Robocity World is a work of fiction licensed under the NCAO Manifesto. Because NCAO is a custom license not covered by legal protection, CC-BY 4.0 applies as an ancillary license and therefore it takes legal coverage.
‘Robocity World’ is not a registered trademark and will never be. I’m strongly against trademarks as I believe human beings are entitled to co-creation and the sharing of ideas and creative or intellectual work.
That I know of, ‘Robocity’ is not a registered trademark and it has been freely utilized over the decades as a generic term for ‘city of robots’ and for works of art and/or fiction.