The price of phones in China is less than outside of China, and this price difference is tempting to buy them. But for some reason it should not do: Xiaomi disable ability flash Global ROM on Chinese phones.
The MIUI user interface in China replaces the Google service (which is banned in China) and brings other changes. Gray imported handsets (available in low-cost China, and elsewhere) usually have a way to activate the Play Service, but nevertheless, they still have a handful of apps and services that you use to use them. So they are basically full of inappropriate applications that reduce the ability of the phone. Global gadgets are specifically designed for overseas markets, just like the ones you need, and there's no sign of the Chinese writing anywhere.
So far, it was possible to change the phone's ROM after it was purchased, but now this change is not possible. You can no longer flash the Global ROM for phones that have Xiaomi for the Chinese market, or for Chinese smartphones for a global phone (some of which get updates faster).
It is still unclear how far the phones are affected by this change. However, there are reports that users can use an unblocked bootloader to flash any flash drive that they want to flash on their phone.
Following this, Xiaomi recommends buying your phones from official stores or authorized dealers. It should be noted that this issue remains unchanged for mobile non-xiaomi.