I have managed to do this using IMAP.
For each provider, I think it's easiest to create a one user account first, especially where the auto fill settings work. I would test to make sure those accounts work. I would then note the smtp related settings you want to use. After doing you can modify the account to use the new smtp settings. You have to uncheck the box that says "Use the same user name and password for sending email" After unchecking the box new fields will appear that are needed for entering the outgoing specific smtp info. I also found it helps to be logged on to the web mail site for that address while doing this. I suspect there is some verification going on and you need to be logged for the saved information to be accepted.