[ajro]

You can't do 2-factor authentication with applications that don't support it. You can't do it with, for example, IMAP, period.

I am not sure about that at all. For imap for example you could be required to submit your password followed by one time code in single login command:

. login youraccount yourpasswordyourotp

So in the password prompt when the client connects you should type in your password + your otp in one step. But that is still two factor authentication. Of course there is no sense in caching/storing such password. It would be less convenient for sure but saying that you can't do 2-factor for imap is exaggeration.