AOcrayon is a third-party tool that was made with the intent to help players of Anarchy Online change their base chat text colors easily, without mucking about with complex xml file editing.
Change your chat colors to whatever you want them to be. Advanced mode for changing any color listed in the ChatColors.xml file. Doesn't do anything to your output, so don't worry about someone else being annoyed with your changes. ChatColors.xml file from 17.0.0 bundled with the program.