I'm looking at using multiple Teensy, possibly only 4.0 but maybe 3.6 too, they would act as MIDI devices and would need to be connected together via USB, either 1-to-1, either 1-to-many through a USB hub, and exchange MID data.

Also those teensy would be powered via their regular USB port I guess unless this isn't possible when using their USB host port?

So my questions are:
- is it possible to connect 2 Teensy together, USB host to USB host?
- is it possible to connect multiple Teensy, their USB host to a USB hub?