Question : How do I accept all mail to a local user but still allow outbound mail

I have a FreeBSD server running sendmail and would like all mail from specific machines to be delivered to a local user(regardless of to/from domain).  After making some modifications to the messages to go outbound and dropping them in the queue, Sendmail should send anything outbound from localhost.  I have had outbound mail from local host going out, and I have had a catchall to accept ALL mail to specific user, but not both.

Answer : How do I accept all mail to a local user but still allow outbound mail

then why not u try fetch mail for incoming catch-all purpose?