User blog comment:Thomasfan502/Season 8 Discussion Blog/@comment-24027341-20180316163135/@comment-31892545-20180318010816

I’m so on board with this art style. My theory with the changing of skin tones is that their may be different artists working on different pieces, and therefore different interpretations of the character exist.

Although we’re not talking about animation here, Sailor Moon had so many different animators switching out on a weekly or even daily basis. That could be what’s occurring here, and I wouldn’t be surprised. If this is what’s happening, as long as a piece looks close enough to the character, the design team could approve it.