[Andrew Hollister]

Compressor keeps presets in .setting files. If these .setting files are in
Your user name/Library/Application Support/Compressor/Settings/
…you can use them within Final Cut Pro X.

From this article https://alex4d.wordpress.com/2012/12/07/fcpx-using-compressor-preset-as-custom-share-destinations/

Now if only we can access and tweak the built in Destinations, I’d love to tweak the Vimeo preset.