While PoE is sexy and very good feature; not all devices support it and one usually have to run extra adaptors. The other down side is one cannot combine it with Powerline driven ethernet.
There’s a solution to all that:
https://www.reddit.com/r/pihole/comments/evaie1/dual_pihole_configuration_now_with_poe_for_that/
UGREEN Ethernet Adapter
https://www.amazon.com/dp/B01N1X28F1
Doing the next round of upgrades we’ll be testing these for the pi cluster.