No, there is no hotkey function on the US3344I. You must use the remote selector pushbutton to switch devices. There is no internal CPU to process hotkey commands.

But you can use port selector or RS-422/RS-485 Terminal Block on the rear panel for port selection. 

RS-422/RS-485 command: 

1.        [sw], for port switching , sw (switch to the next port) , sw p01(switch to the port1) 

2.        [info] display current hardware status