How to batch forward messages from Mail.app

I get mail forwarded to my OS X Mail from an Outlook account at work. I use my Mac to reply to messages directly from Mail.app and now I want to forward all my sent mails from Mail to my Outlook account for filing.

Is there any way to do this that's easier than individually forwarding all the messages manually? I want to keep all the messages separate.

You can set Rules in Mail.app preferences to take actions on emails. What should work is a rule configured like this:

You would just need to fill in the to: field with the account that should be receiving all email.

Another option is to forward mail from the source. If the source is iCloud, you can Forward all messages automatically. If you use Gmail, Gmail can do it too.