Will the Hololens 2.0 use ARM instead of Intel?

Those are valid thoughts, especially given Intel giving up on the low power processors. They have Core m or ARM as options. I think you get more bang for the watt on ARM.

Windows 10 on
ARM
:

IOT, Connected PCs, likely a new portable device and possibly a new HoloLens?
 
AMD has an ARM processor for enterprise use; I suspect that they are keeping an eye on the Qualcomm 2-in-1s and might launch an ARM/Vega CPU if they think it will sell.

A new Tegra might be in the works too.
 
There is no doubt in my mind that the next version of HoloLens will house an ARM chip. They cancelled the V2 of HoloLens last year and pushed the next revision to 2019. In some ways it makes sense as they announced Windows on ARM a few months later. An always connected headset with C-Shell solves a lot of problems the first version has.

I had the opportunity to try out a HoloLens for the first time today, it was a very cool experience.
 
There is no doubt in my mind that the next version of HoloLens will house an ARM chip. They cancelled the V2 of HoloLens last year and pushed the next revision to 2019. In some ways it makes sense as they announced Windows on ARM a few months later. An always connected headset with C-Shell solves a lot of problems the first version has.

I had the opportunity to try out a HoloLens for the first time today, it was a very cool experience.

I hope you get to try out a HoloLens 2. It's an amazing improvement over the 1. As to your question about processor it is in the Snapdragon 850 family.