It looks like the new Google's Pixel 4 watch comes with yet another incompatible change in charging technology. This is a ridiculous situation. The original Pixel Watch used one type of wireless charging. Then the Pixel Watch 2 & 3 removed wireless charging and swapped to a different charging mechanism. And now the 4 has changed again. So three different charging cables in under three years.…
I had one with solar and one without, I think the solar is mostly useless.
It only takes a short time to charge it up with the USB charger (proprietary charger, FYI) so I don’t think it really matters.