Does the Creator anchor support USB-CDC-EEM or Ethernet emulation over USB?

The Creator anchor doesn't support USB-CDC-EEM or Ethernet emulation over USB. For a scalable setup with Ethernet communication, we recommend to use our Enterprise solution.
If you want to stay with the Creator product, you can also use a Raspberry Pi and use the pypozyx library to communicate with the Creator anchor and relay the information over the Raspberry Pi ethernet connection.

Does the tag provide uncertainty information about localization (covariance)?

The tags do not provide information about uncertainty.