When you move any plantt from inside to outside, you need to gradually introduce it to full sun or they can sunburn. I don't see anything wrong with your Aloe. It should not be bright green living outside unless it is in full shade. Aloes change color in response to light levels, water availability, heat, etc. It is a stress response, but does not mean the plant is sick.

I actually like the grey/brown color more than the bright green it turns inside. I've got one outside that looks very similar to yours outside. Your conditions inside are abnormal. A bright green plant is not the way it should look.

Brad