Ok, it's my first time posting here, and I'm stuck at an impasse and I'm not sure how to solve it.

What I'm try to do is use my Teensy 3.2 as a keyboard to send key commands to multiple different phones which are acting as hosts over usb.
The reason I'm doing this is that we refurbish phones and when we flash the software on the phones our techs have to go through a lengthy startup process to get to the home screen.
I've already figured out that you can use a keyboard at this process (I think because the phone acts as a host, and the usb keyboard as a slave) to skip this process.
I programmed up my Teensy with the list of commands to send and it works if it is only connected to one phone.
My next step is to hook up the Teensy to a hub or splitter and send those commands to multiple different phones all at the same time.

This might not be a question specifically about the Teensy but more about USB architecture. Essentially what I'm trying to do is to send multiple keyboard commands (as a single slave device) to multiple different host devices.