It’s also obvious, not sure why it isn’t a thing. For example:

• orange band means it supports “fast charging” and a number indicates the voltage supported
• black indicates “high speed” data, and a number indicates the speed
• green indicates display out, and a number indicates resolution

So you’d have a colored band always at the same spot (for color blindness), and a number on either side of the plug in the color band. Maybe use Roman numerals so it’s easier on the eyes. No color band would indicate basic features (5v charging, slow data transfer, no display out).

Previous USB standards also used colors on the plug to indicate speed, so it fits right in.