The WAN port is not configurable at this time. Asus has started implementing SSH support into the stock firmware, so I don't want to waste my time implementing this, only to see Asus implement it in a different way a few weeks from now, forcing me to rewrite my code. So I'm waiting for them to finalize SSH support on their own end.
Asuswrt-Merlin: Customized firmware for Asus routers
Github: github.com/RMerl - Twitter: RMerlinDev
See the sticky post for more info.