Ah right - I don't really see that as an issue (when do you ever want to split them in a way the cable becomes problematic? also you now have two individual units to hook up with battery)
I guess this is why you don't really see many attempts.
I’m very broad so my keyboard is split wide, it comes almost to the end of the cable so having two wireless halves would make a nice difference. The shield looks promising, but with all of my other projects I just lack time to hack together a keyboard.
I guess this is why you don't really see many attempts.
But maybe something like this will do the trick?
https://wiki.seeedstudio.com/Grove-Serial_Bluetooth_v3.0/