Mouse mode has been rumored, and some leaks have shown what could be an optical sensor on the joy con.
Also, if you take your current joy cons and place them on their side like that, they surprisingly feel pretty great as a mouse. Shoulder button for min click, and your thumb hits the four face buttons. I could see it working pretty well.
Correct.
I would like to think you could pair old joycons to it in a pinch since outside of that new button on the right joycon they look exactly the same.
But, yeah, when it runs out of juice you’d have to stick them back on the old switch or use a third party charger.
But we’ll see, for sure.