Example smtpd.conf for relay different Gmail accounts

smtpd.conf

# $OpenBSD: smtpd.conf,v 1.9 2016/05/03 18:43:45 jung Exp $

# This is the smtpd server system-wide configuration file.
# See smtpd.conf(5) for more information.

table aliases file:/etc/mail/aliases
table secrets file:/etc/mail/secrets

# To accept external mail, replace with: listen on all
#
listen on lo0

# Uncomment the following to accept external mail for domain "example.org"
#
# accept from any for domain "example.org" alias <aliases> deliver to mbox
accept for local alias <aliases> deliver to mbox
accept sender "alice@gmail.com" for any relay via tls+auth://alice@smtp.gmail.com:587 auth <secrets>                                                             
accept sender "alice.smith@xyzzy.com" for any relay via tls+auth://alice.smith@smtp.gmail.com:587 auth <secrets>