Seems like there are a bit of interested in the Daisy Chain DC Cable. I went ahead and made it available to purchase online. I was going to wait till I update the firmware with power limiting option before releasing the cable but been low priority.
https://www.reefi-lab.com/product/daisy-chain-dc-cable/
The daisy chain cable are 16 awg wires to support the high current draw of the Uno 2.x Pros. Yes, you can make your own, just use 16 awg wires or thicker to prevent overheating the wires and high voltage drop out. The connectors are 2.5mm x 5.5mm, 1 female to 2 right angle males.
Warning prior to firmware update with power limiting feature, make do not overload the power supply. The combined max wattage must be less than rated max wattage on the power supply.