Users should be able to set local hostnames for networked devices
Eero currently supports the ability to reserve an IP address for a device on the network via its in app "Reservations & Port Forwarding" menu. However it lacks the ability to set local hostnames, a common feature found in many mid range routers offered by the competition. It would be nice to offer this feature instead of leaving it to users to set up their own custom local DNS server.
You can add a "Nickname" in that same section you mentioned which works great.
However router's don't change the hostname of other devices, you would have to change the hostname of the device itself. Like for a PC or Printer, but most smart device's hostname cannot be changed as its hardcoded in their chip so the next best thing is nicknames set on the router.
If I recall, Linksys gives you the ability to change the devices "hostname", but it doesn't really change it, it is also just a nickname. You can test it on a PC, and verify in CMD by typing in: hostname