iPhone 13 pro with ZAA part number

You should buy the phone in the country where you will be spending the most time, because that is the only place the warranty will be honored. The exception is the EU counts as a single “country” for warranty purposes.

But note that a US phone (LL/A) is eSIM only. Any other country other than China, Macao and Singapore will have one SIM slot and support for multiple eSIMs.

The only iPhones that support 5Guc are those intended to be sold in the US, as the 5Guc standard is still not formalized in the rest of the world.

That may not be an important issue for you; low and mid-band 5G is still much faster than 4G/LTE. So unless you need 200+mbps on your mobile device you don’t really need millimeter wave. And even in the US it is not universally available, as its range is in the same order of magnitude as Wi-Fi; millimeter band 5G “towers” (which are actually boxes on lamp posts) must be located every few blocks to get coverage.

It will work in the US, but it won’t support 5uc mode because it doesn’t have the millimeter wave antenna. Phones that support 2 physical SIM cards do not support eSIM.