Having just installed nest hello I wonder what the operating voltage is?
In the UK wired doorbells seem to work on 6v or 8v including the one nest recommend buying
The problem is that nest hello requires 10v to 24v
Luckily I bought a new chime (the one they recommend) as I ended up wiring the new & old transformers together (primaries in parallel, secondaries in series) to get it to work
The wiring instructions were also in the app and like @Maypo52 the examples didn’t quite match
I’m surprised they made it wired but made the chime unusable so the chime is an oversized PSU and give you a secondary chime that you need to plug in
Would love to try the eufy doorbell to compare it properly but it depends on price if they sell it for in same in GBP as USD then I probably won’t, if it matches the exchange rate I probably will, with the 30% off for being a eufycam backer that would make it £89 ($112) & full price would be £126 ($159)