In version 3.x, Esri introduced the Color Vision Simulator tool, which gives mapmakers without color blindness the ability to see what their maps look like to people who experience color blindness. It would be helpful if the legend was included in that simulation so that you could confirm that the end user can match the altered colors with what they would see in the legend. That way, you can confirm that the user is able to translate which category each item in the map corresponds to.