[zooFox]

Probably different solution, but my Amazon Eero mesh allows having a backup WiFi.

There's a primary network that's connected via ethernet and I can set up a secondary network (in my case, iPhone hotspot) as a backup. https://techcrunch.com/2022/09/28/amazon-expands-eero-line-a...

The advantage of it is that it's quite simple and plug-n-play.

Would that work?