The 6027 does not support CAC. But...
A CAC card has nothing to do with email, it is just a method of logging into the printer, and the card can give access to use or block the email feature.
So the printer is set to access email, the card swipe allows you to use the feature itself as well as populates your email login info and sets the from address to your email address to the Email server.
I use enterprise email so I have to use a cac card to send email.
I would like to use the scan and email function on my 6027 but I all I see is imap and pop 3. My google searching does not confirm or deny if the 6027 can support this but the newest document I could find was from 2015.