Cosmo was removed from the Tools menu by default in Looks versions 5 and later on account it would've prevented CUDA playback, but is still built-in in the back-end to retain backwards compatibility with older Looks versions that might've used it.
If you want to regain easy access to Cosmo, you can follow these steps:
- In Looks, go to Looks > People and select Classic Skin Smoother
- Delete Colorista II Pop
- Click the Save Custom Look button in the lower left
- In the Save Look window that drops down from the top, save your preset as Cosmo (or whatever makes sense to you).
You will now have Cosmo saved as a custom look. To apply it, you can select it from the custom looks drawer. If you want to then select another Look preset, you will first need to right-click on Cosmo and select Pin. This will keep Cosmo in your tool chain even when applying other looks.