S'ils ne sont pas géographiquement bloqués en France vous pouvez utiliser ceux du CIRA. Ils ne devraient pas être censurés. Reste à voir la latence transatlantique.
If you are using zigbee you should check Sinope Sedna Walter valve with the optional water flow sensor. It is supported in zha using quirks from claudegel on github.
Just make sure you select the ZigBee one since their WiFi one need their proprietary hub to work.
Canadian here who used both small and big providers with pixel phones (3, 5 and 7 pro) bought directly from Google (not financed through the provider).
Not all smaller providers provide 5G but they all have LTE or LTE+. I had 5G working with my Pixel 5 without issue when I was with one of the large providers. I'm with a smaller provider now on my Pixel 7 pro and have no issue connecting to LTE(+).
But, you also mention the Pixel watch. I never used a watch with a sim card and I have to say that it is not always clear from the provider's website if they are supported or if they will provide a esim for them or not, and at what cost. This is something that looks a lot more straightforward when with Apple than Android.