So I was going through ToS:
Service is limited to the options available in the country where you request service
If service is not available in a country that is not the country of purchase, you might be responsible for shipping to facilitate service in a country where is available
For international service, Apple might exchange products and parts with comparable products that comply with local standards (aka, you got an eSIM only US phone, you might get back a SIM European phone and losing the fancy 5G that works in teh US only anyway).
From their wording, updated on Sept 12, it seems that they do cover international AppleCare+ as long as service options (so not necessarily applecare+) exists in the country where you request.
E.g. I'm living in Poland and we have AppleCare+ only for Mac and iPad, but we do have authorized Apple service for any other device. My American AppleCare+ iPhone can be serviced locally through them.
I'm in the same boat, buying my iPhones from the US cos european tax is crazy 🤣