I used to think there was something like a standard color code, but then I learned that trailers were different. Then I bought stuff from Amazon (no instructions) and learned that the UK, Europe (IEC) and China also have unique codes, and they are different.
So now I can figure out my Chinese stuff. My boat, on the other hand, has parts from Asia, Europe, and the US, and there is no color code I can derive. So I stick with black and red and label the ends where they are not obvious.
(BTW, the reason ABYC does not use Black for the 12 V negative is to avoid confusion with the 120 V hot. My boat doesn't have a 120 V system, so I'm not worried. The IEC also specifies a different color for the high voltage neutral (blue).
