You can do policy routing (but without port based rules) in advanced properties of your FW
Or a better way is to do that with NAT rules and Netlink in your FW policy.
I will try that
It is possible to use policy routing, or if you configure a multilink, then you can use QoS classes to select default netlink for each type of traffic. This has the added benefit that the other route(s) can be used as backup.