Here are my NAT rules for HA/Mosquitto:
add action=masquerade chain=srcnat comment="Assistant, Mosquitto SNAT" dst-address=192.168.22.16 dst-port=8123,8883 out-interface=bridge1 protocol=tcp src-address=192.168.22.0/24
add action=dst-nat chain=dstnat comment="Assistant, Mosquitto DNAT" dst-address=!192.168.22.0/24 dst-port=8123,8883 protocol=tcp to-addresses=192.168.22.16
add action=dst-nat chain=dstnat comment="Letsencrypt DNAT" dst-port=80 in-interface=ether1-wan protocol=tcp to-addresses=192.168.22.16 to-ports=81