You had a question regarding editing the uEnv.txt file so I gave you info on that.
As far as the config-pin issue, is there anything for the pin seen under “/sys/devices/platform/ocp/” for the pin you are trying to use the config-pin tool with?
This is what I see on a BBBlack running Buster and a 4.19.94-ti-r51 kernel:
$ ls /sys/devices/platform/ocp/ocp:P8_08_pinmux/
driver driver_override modalias of_node power state subsystem uevent
$ config-pin -q P8.07
Current mode for P8_07 is: default
Using the universal-io version of the tool:
$ /opt/source/bb.org-overlays/tools/beaglebone-universal-io/config-pin -q P8.08
P8_08 Mode: default Direction: in Value: 1
I suspect the pin you are trying to run the command against is not listed under “/sys/devices/platform/ocp/” . Have you configured this pin?
Powering a PocketBeagle from a powered USB hub should be fine.
Jon