I believe they are already encrypted, see below:
from EXODUS:
Where are my private keys stored?
The private keys to your blockchain assets are generated and encrypted locally and stored on your computer ONLY. These keys never leave your computer, they are never stored on the cloud, and they remain 100% for your eyes only, 100% in your control.
http://support.exodus.io/knowledge_base/topics/where-are-my-private-keys-stored
Nice, thanks for the tip.