Alternatively change it so if you apply for a name change then the sex offenders register, the PNC, DVLA, Social services, DWP and passport office are checked and informed of the change so records can be amended accordingly.
OG, yes you can call yourself what you like, many criminals do even when arrested even if known to the Police but it is getting increasingly difficult if you want things like Bank accounts or Dole.
Perhaps the law should be changed so you get goal if you deliberately try to avoid such registers?