Greetings,
Sadly, no, there is no way to change appearance. Due to the nature of the game (the fact it is all pre-rendered, and even then, not in a 'paper-doll' way like most VNs) makes it very time consuming to offer those options. I understand that desire, but I just do not have the manpower, CPU power, nor the time to re-render every image of the player character with different looks.
My next project does have a bit more player character variety, the player can choose between three ethnicities and three genders. That's the benefit of going in with it planned, but when I started SI I was just starting out with rendering and didn't want to bite off more than I could chew out the gate.
So, all that said, for Starship Inanna, it is not in the cards at this time. However, if/when I go back to remake Episodes 1 and 2 it may be something I will do. I can't promise I will, but I would like to, I'll have to see how much time it would take.
~DrMadDoc47