iPhone XR Issues with iPhone XR model no. abroad?

[SuprStrat]

Do any of you have had (or know of) issues with iPhone XR (mod. no. A1984) abroad?
Apple sells A1984 in the US and another model no. (A2105) for Europe and the rest of the world. Since I'm in the US now, that's the model no. I would get from any store, but at some point I will return to Italy for a significant period of time and I'd like to be sure I won' have problems with cellular reception AND warranty.
To my understanding, Apple warranty has a worldwide coverage, but I also read otherwise on Apple forums.

 

[AppleHaterLover]

The US model won’t support all of the LTE bands being used in Europe (and around the world), it doesn’t support band 28 I think. So that’s an issue, though I don’t think you’ll be losing a lot since it is only one of many bands.

I’ve heard that in some countries Apple is now honoring the warranty for model numbers other than the one sold in that country, but I have no idea about the situation in Italy and the EU.