Post-launch edit. I finally bought a Vemont 5 in 1 USB-C adapter with Ethernet. Works with the provided power adapter, no need for Power Delivery or fancy technologies. Other hubs need PD power adapters and won't work on a regular 1.5A or 2A USB adapter.
The new Android TV from Google does not include Ethernet power adapter to cut price down (at least in the US, in Europe it's 70€), so... what are the options given it features just one USB-C?
There is a new official 100Mbps power adapter , similar to the one bundled with the previous 4K Chromecast Ultra. It's $20, that's paying a 40% overprice to get 100Mbps Ethernet. Feel they should have included it, specially with 4K game streaming in mind.
Let's discuss more options...
I know there are some USB-C hubs with Power Delivery, Ethernet, card readers and so on, usually made for laptops. Old Aukey 5 in 1 hubs work but there are some comments stating new revisions don't... Feel like they're overkill anyway, but some are priced similar to the official adapter yet provide many more features. They're also clunky and it's another box.
Also, is there any chance that the old micro-USB power adapter from Chromecast Ultra would work here with micro-USB to USB-C adapter?
Edit: It's been confirmed that there's no way to make the old Ethernet adapter work with the new Chromecast. Source here .
Maybe we could wait a few days and we'll get the official response.