pass in on egress proto tcp from any to egress port 80 rdr-to 127.0.0.1 port 8080 pass in on egress proto tcp from any to egress port 443 rdr-to 127.0.0.1 port 8443
You might want to block direct access to 8080 and 8443:
block return in proto tcp to port 8080 block return in proto tcp to port 8443
Restart pf:
pfctl -f /etc/pf.conf