Mobile routers: USB tethering and band control

I'm considering buying pocket mobile 3/4/5G wifi hotspot and to install OpenWRT on it.
But first I have to know two things.

  • Assuming device allows USB tethering, does OpenWRT support it?
  • Is it possible to setup automatic selection of cellular standard (EDGE/UMTS/3G etc.) based not on data speed, but signal strength?

@ngc3o34, welcome to the community!