> media converter

A proper 4-end-device-port media converter:

https://www.amazon.com/NETGEAR-5-Port-Gigabit-Ethernet-Unman...

No win. Device needs power. I'd hoped for passive splitter

There is the UniFi NanoSwitch[0] if a dumb switch with passthrough power will work for your usecase. Works on anything 12-24v.

0: https://store.ui.com/collections/operator-airmax-and-ltu-acc...

Yeah, PoE makes this sort of thing much easier. The Unifi Switch Flex Mini [1] is even cheaper, but requires "real" PoE (not passive 24V), and doesn't pass through PoE. The various in-wall access points [2] are PoE powered, PoE pass-through, flush mount to a wall plate, and have an integrated four-port switch -- depending on use case the WiFi is almost just a bonus. If you have ethernet cabling in your place, it's definitely worth putting PoE on it for the options it opens up.

[1] https://store.ui.com/collections/unifi-network-switching/pro... [2] https://store.ui.com/collections/unifi-network-wireless/prod...