The WAX206 is so easy to flash with OpenWrt that I am not sure everyone that tries to do that even knows what ssh is.
If you are using a Windows PC you can for instance download and install PuTTY on your PC, connect as user admin (no password) via ssh to 192.168.1.1 and afterwards install Luci as described here:
Due to the fact that the factory image does not contain Luci and you need to install this first there is no way to avoid this step from my understanding. Even if you decide to flash the rc2 image next.
I just came to the conclusion that I was wrong. It should be possible to upgrade from the factory to the 23.05.0-rc2 firmware either using the command line or by the TFTP method as well but I never tried that with the WAX206 myself. That might be good alternatives in case you face problems to set up Internet access to install Luci