The main difference between indoor sun and outdoor sun is the UV, which is mostly blocked by regular window glass. So maybe your plant took a hit of UV that it was not prepared for.... that would explain some color change and maybe a stress response. These plants vary a lot from season to season and summer is typically when they rest. So you may not see much new growth or recovery until the fall. Aeoniums change color and shape as part of their cycle. A stress response is not normally anything to worry about but your plant will do best if you make gradual changes in exposure, rather than sharp and abrupt ones. My usual destination when I move indoor plants outside is either a bit of morning sun (only) or filtered light. Your plant will enjoy a much bigger pot when it picks up again in the fall.
