47. Mon Mothma
Yes, the person who tells you that many Bothans died to bring you this information in ROTJ has a name: Mon Mothma.
Like many leaders in the Star Wars universe overall, Mon Mothma has white as a major color in her palette. (Leia is the other obvious example, and you can easily argue that the Naboo queens’ looks are dominated by their white-painted faces. Even Imperials sometimes wear white.) Like Leia’s ANH costumes, Mon Mothma has basically one costume that gets repeated any other time she shows up. This includes her scenes from ROTS, though they were cut, and her appearance in Rogue One.
Go on, we’ll wait. Here’s a Rogue One trailer. Although the ROTS iteration adds some different details on the shoulders, it still has the chains and medallion and keeps the white scheme.
However, for her, it works. Because she can’t be described as a major character in her first two appearances, it makes sense that she has the same look each time. When we see her, we know she’s the politician who helps lead the Rebellion. Simple and to the point.