Modify the nationality of an Apple ID

I wanted to change my account for an American store to a Chinese store a long time ago. I wrote a letter asking apple for support and got a reply as follows: there are two ways. One is to create a new Apple Store account, and the other is to change the account's nationality. If it is the former, we will not say much about it. See how to create an Apple id in iTunes.
Http://support.apple.com/kb/HT2731

Create an iTunes store, App Store, ibookstore, and Mac App Store account that does not need to be associated with the credit card number
Http://support.apple.com/kb/HT2534
If it is the latter, note the following:
1) if the account contains a fraction of the store, use these points before changing the nationality.

2) download all purchased content. The rental item expires 30 days later. For details, refer:

Http://support.apple.com/kb/HT1657

3) You must select a payment method, such as a credit card or debit card with a valid bill address (new nationality ). The iTunes store discount card for new nationalities is also available.

4) after changing the nationality, the store of the old nationality will not receive the upgrade notifications of the purchased app. However, you will receive an update notification that has been installed on the device.

5) If you subscribe to iTunes match, you cannot change your nationality unless the subscription expires.

6) If you have purchased the season pass, you cannot change your nationality unless the entire season expires and the last episode has been added to the iTunes store.

7) after changing your nationality, if you have used iTunes to synchronize the cloud, the purchased items will not be displayed on the "purchased" page of iTunes.