So when Anakin Skywalker was a Jedi he looked like this
But turning to the dark side changed his physical appearance. Most notably his eyes, which became yellow (a very typical Sith transformation in many species)
And while I know that Wookies are not supposed to be able to be force sensitive and therefore cannot become Jedi or Sith, all I am saying is that
…. You know?
There is literally no way I could have guessed where this post was heading