Nope. Favorites in particular are stored as metadata. There's no way way to export then unfortunately.
Your best workaround is to, unfortunately, create a new collection, and then in your favorite list mash X and down in sequence until they're all added to that new collection. I had to do it at one point for 500 games... Felt like a quick session of Hyper Sports/Track and Field.
Then if you exit ES you should have a file with those games under ~/.emulationstation/collections
Sorry that's not as helpful as it could be.
What's the use case, if I may ask?
Thanks.