Just got a marketing email from Murena and they are advertising the FP6 in the USA with a $60 discount. I bought one when they first went on sale in the usa and I love it. You can run AOSP android or /e/os on it. I’m running /e/os with the fossify launcher and it’s pretty great. Battery life is probably the best part though, I can easily make it 3 days without charging.
https://support.fairphone.com/hc/en-us/articles/9779766652689-How-to-set-up-4G-and-Wi-Fi-Calling
It exists, but as you found, that doesn’t mean it’ll work. You’ll really just have to test it yourself, so buy from someone with a return policy.
If your carrier offers microcell stations, maybe drop one of those in your house so that you have regular cell coverage.
Thanks for the link, and good suggestion. I’ll look into that.