Check out decommissioned Brocade or Ruckus switches on eBay if they're available in your region. There's a thread over on ServeTheHome with a licensed feature unlocking method that'll get you fully enabled hardware for cheap cheap cheap prices.

On my ICX6450-24P I see like, <20W power use while shoveling packets through four 10G ports. PoE drives usage up, obviously, if I'm supplying power to things with it.

If you can find them the ICX7250 is a baller homelab switch, I paid <$250 for mine and I'm putting the 8x10Gb ports to good use. Low power draw here as well.

If you want bigger the ICX6610 is a power hog but offers a couple of 40Gb ports as well as 8x10Gb. These draw significantly more power, they're powerpc rather than arm, and are loud compared to home gear but they'll let you link a bunch of machines at 10Gb as well as two at 40Gb - which is awesome for a NAS and/or firewall. I want to say mine drew like 50W at idle so they're not cheap to run over time.

I've also considered rolling my own whitebox router so I can connect 2.5 and 5Gb gear to the rest of my network but it's not that much cheaper than just buying a cheap chinesium $200 dumb switch with 4-8x 2.5Gb ports and a couple of 10Gb uplinks.