If Larian doesn't add this option I'm guessing mods will take care of it. (And maybe there are mods for it already?)
Sadly I believe (from what I have read from modders) that it isn't something that they can currently do.
There is a mod that exists (2 mods actually) but they are
very gimmicky and you can only change some parts of your appearance (e.g., you can't change Hair, Hair Color or Skin color, for example). It also comes with various bugs (e.g., being unable to respec at all!). I remember there is a separate
Hair Change mod but it changes the hair of every single NPC along with your own hair... which is plain stupid having everyone with the same Hairstyle in-game. It also doesn't change your character portrait. No idea why someone would think this as a solution to changing our appearance...
As it stands right now, only an official Larian update can bring a functional Character Appearance Change.
