If I buy an unlocked GalaxyS7 and have a Verizon SIM card installed, will Verizon give it full functionality? I ask because I have an unlocked Nexus5X. form Google. Verizon installed a Verizon Sim, no problem. But I later learned, the hard way, that Verizon does not provide a full feature SIM, i.e. I cannot make international calls even though I have an international plan and I can not use phone via my home internet wireless network - only Verizon cell network, etc. I don't want to run into the same problem with a new phone. Thanks.
There are some features, like Wifi calling you mentioned, that only a Verizon branded android can use. It is not blocked on the SIM card, rather it is the branded devices being programmed for these features while non branded are not.