How to get my final game to look as "unlit" as possible?

I’m currently working on a 2d sprite game and I learned that you cannot use viewmode unlit in the final package of the game. So is there a way I can fake it or disable my lighting somehow? I have a sky sphere in my scene, but otherwise there’s nothing related to lighting.

I want to make this:

Look as close to this as possible:

Thanks for the help! :smiley:

EDIT: I’m using the orthographic camera if that makes a difference.
EDIT #2: The huge light flare only seems to happen in orthographic mode. Any idea why?