The SOLID and HOLLOW stands can accommodate a USB port in the rear and looks good if you add an LED as the photo illustrates. I'll include links for the USB port and plug. If adding an LED I'd use a 1K resistor for a dimmer light or 450-470 ohm for full brightness.

The hollow stand is just that - completely hollow, with slightly thicker walls. The solid stand looks great with about 10% infill. It gives it a nice diamond pattern. The hollow design is almost no infill but I'd go ahead and use 100% infill. Both have 4 or 5 WALL LINE COUNT.

The USB socket is currently on the right rear. If you'd prefer it to be on the left rear you can mirror it in your slicer.

NOTICE in the photo of the USB socket that the end of the black plastic cover is cut off of the top and bottom and the lower half has even more cut away to allow the power wire and the LED's wire to pass out the back.

One of the photos shows the soldered leads on the USB socket. Note the gray notch indicating the positive lead. The two middle leads are the data pins. Some phones and tablets require them to either be shorted together or have a resistance between the two for a charge to begin. Iphones require this. Make sure you short them together.

USB Plugs -- https://www.ebay.com/itm/10x-USB-Plug-Male-Mounting-Assembly-Solder-Pin-Connector-Cable-Pack-of-10pcs-AF/292295278149

USB Sockets -- https://www.ebay.com/itm/10Pcs-Type-A-Plug-USB2-0-Jack-Black-Plastic-Cover-4-Pin-Female-Adapter-Connec-ng/332672226746

22GA power wire -- https://www.ebay.com/itm/2-Pin-Black-Red-PVC-Insulated-Connect-Cable-Wire-for-3528-5050-LED-Strip-Lamp/312062015929