How do I install apps (transmission, plex) with differnt IPs?

I’ve just migrated from core to scale and struggle to understand all the parameters while installing transmission (assuming I’ll experience the same with plex)

Truenas has the IP 10.2.42.222 and I want transmission to be reachable at 10.2.42.223

In the setup I see “host IP” twice, but typing in 10.2.42.223 doesn’t work
Is this not possible to do from the “installer”?
How do I accomplish this?

Add the addresses you want to the main network card as an alias in system/network

Then the address should be available as a host IP in the app configuration