FA-06/08 Firmware Version 1.03 adds WIFI connectivity using the ONKYO UWF-1 Wireless USB Network Adapter.
https://www.rolandcorp.com.au/support/by_product/fa-08/updates_drivers/350580
https://www.amazon.com/Onkyo-UWF-1-Wireless-LAN-Adapter/dp/B004WR125O
The Jupiter-50/80 and Juno-Di/Gi had this same capability, but they all used the WNA-1100-RL adapter. The WIFI connectivity was primarily for Ad Hoc connection to apps on iOS devices. It could not be used for direct wireless connections between keyboards, because as Gary has already explained, one end of the connection or the other must be running "HOST" intelligence, either in firmware or software, and the keyboards do not have that intelligence. I was able to connect my Jupiter-50 to my Juno-Gi via WIFI, but that was using my laptop as the "HOST" intermediary with MIDI/Audio director software to complete the connecton. The whole point of the Ad Hoc connection is that it allows direct WIFI connection from the keyboard to the "HOST" device without needing a WIFI router. Essentially, the "HOST" device acts as the WIFI router, so you can use it on a gig without having to rely on the venue providing access to a WIFI router. For me, with the expense of the two adapters (approx. $40 USD each), plus all the tedious/contrary connection set up, it was a lot quicker and easier, and much less frustrating, to do it with USB cables to the laptop, and would have been a lot cheaper, if I hadn't already spent the money on the adapters, but I figure. if nothing else, it gave me the experience to discuss it in situations like this. Now, using it for what it was originally intended, connection to iOS devices, made a lot of sense, because it avoided having to use that flimsy, unreliable iPad Camera Connector Kit.