Importing Knights would simply be moving a Knight file from one account to the other. There'd be a "Import" button on the knight selection screen. After you click it, you select the knight to import. After an "are you sure?" or two, you'd choose between whether you want to import it to a Steam account, a Sega Pass account, or a normal SK account. Click any of them, and you'd have to enter the username AND THE PASSWORD of the account you want to import it to. You could import knights as much as you want, but it wouldn't copy it. Once you import a knight, it's gone from the original account. But you can import it back if you want.
Why would you want to do this? The most prominent reason is bonding a knight you had before steam compatibility to your steam account so you can get all of the cool steam-related stuff without having to restart the entire process. Another reason would be just moving it to another account if you want, either as account separating (for security reasons if you have local players) or merging accounts. Yet another reason would be if you don't play as knight 2 anymore but still play as knight 1, and someone would want knight 2 because he has cool equips, so you import the knight to his account. (of course, you'd need his password, but he could probably change it to something temporary for importing it.)
What say you?