Name color, unless I misunderstood the system, actually can be changed at the forge. This is because text color is determided by a few variables written in front of, and behind the colored text.
This article goes into detail a bit more, but essentially you have to write <c---> in front of the name, and </c> after it, with each - being the RGB color value in ASCII code. I'm pretty sure it works with familiars, so I don't see why it shouldn't work with the mythal system.
Now, item description, I believe that -could- be changed by a job system scribe, but I believe that carries certain... Problems. Like usually just spamming the commands in chat until you finally roll a high enough number to succeed.
That said, I could be wrong about both.