With iOS 12.1 available to anyone the latest iPhones models (iPhone XS / Max & iPhone XR) are able to make use of a second sim (physical or as an eSim) and phone line. The setup is fairly easy but I ran into the issue that something got very messed up deleting my iMessage activation and seemingly no way out.
If you happen to run into these issues, it appears to result from Apple still wanting you to use a physical sim card instead of the eSim as your primary line, which is what I was doing since no US carrier supported eSim. Once I got my new iPhone XS I scanned the eSims QR code for my german contract and had it setup right away. It almost feels a bit too futuristic. Debugging this can be very tedious but these steps worked for me
All of this is still a bit tricky but once setup I had no further issues. I was able to switch the lines for calls right away and have been using that sweet sweet LTE at a local rate for two days now without any issues.
I have been waiting for such a feature for a while and it’s great that Apple makes this easy because the Telco companies around the world sure wouldn’t push for something like this in a million years. They simply make too much money from international roaming and it’s time for that to end!