I think you can make two same units with another names and then remove remove the old one and add the same unit with the other name(keeping all stats, skills, items).
Technically you could replace a hero with another one having different proper names. This would take enourmous work if you want to actually use the hero for anything non-cinematic etc.
Finally finding about some of the bots that are flooding the users online - bytespider apparently is a huge offender here - ignores robots.txt and comes in from a ton of different IPs
Ghan has said he has fixed this. Monovertex please confirm this fix. This was only a problem with people that had signatures in the upper levels like not the special members but the respected members.