Display Recvd and Sent Items in Same folder?

[Phill]

Is it possible to modify an existing Mailbox folder or create a new one
that by default displays both incoming and outgoing messages in the
same folder?

 

[Brian Tillman]

Is it possible to modify an existing Mailbox folder or create a new
one that by default displays both incoming and outgoing messages in
the same folder?

As opposed to having the outgoing messages in the Sent Items folder? Sure.
Create a rule that copies each outgoing message to the same folder where you
have your incoming messages, like Inbox.