I believe what you're talking about is the plastic surgery mirror already in the game. To get it, put boolprop testingCheatsEnabled true on and then shift click the newspaper. When on the newspaper, click career rewards, and then to show business.

Then go to your sim menu (the treasure chest thingy) and it should be on the first page, if not, look through the pages and you should find it.

You can use this to change your sim's facial features.. but not eye color.

Hope this helps