Catwoman Mask with Optional Colors is an add-on for Fem V that gives her a Catwoman Mask and lets you change her mask into any color you like. You just need to install it and you're good to go. The addon comes with a list of all the colors you can use. You don't need to download any other add-ons to use it.

You can find the installation instructions on the homepage. The instructions are very easy to follow. You just need to download the app and install it.