iphone xs max dual sim (model A2104)

I recently received my A2104 and have been experimenting with it. I have placed international sims in the phone (Onesim.com) in each of the dual sim slot. I've inserted it as primary and secondary and it works perfectly. I have also had numerous discussions with both AT&T wireless and apple. If you are using a sim card from Greece there is no question in my mind that the dual sim phone will work just fine. I am using AT&T wireless in my primary slot and the international sim in the secondary slot making calls to Europe without a hitch. I was also told by AT&T and Apple that once the esim is activated it becomes transparent to the other network you are connecting to so long as the system has a roaming agreement with your local provider (assuming you will be using the esim as a US phone). If you are considering the US model with Esim, You may have trouble using it in Greece if that is the only account you have. If you place a Greece nano sim in the phone it will work fine so long as you have the simfree unlocked model. I bought the A2104 because I just didn't want to hassle with the possibility of an issue. Having said that, now that I know about the "transparent" esim, I would consider the US model and save some money. I had to pay a premium buying the HK version and have it sent to USA.