How to get a physical SIM for foreigner.

mufufu wrote:

I am Japanese. When I visit the United States, I would like to purchase multiple physical SIM cards from T-Mobile. Can I purchase physical SIM cards by presenting my passport and credit card? I prefer to purchase physical SIM cards rather than eSIM. I have heard that physical SIM cards cannot be purchased unless you are a resident of the United States or hold American citizenship, so I am concerned.

That only applies to postpaid services, which require your Social Security Number or a Tax Identification Number, a credit check, and a US debit or credit card of you want to pay through the website.  

Prepaid SIM's can be purchased by anyone and are primarily used by visitors to the US.  You can purchase as many of these as you want from most retailers or at a T-Mobile store.  Just make sure you specify that you want prepaid SIM cards because postpaid SIM's can't be used for prepaid service and prepaid SIM's can't be used for postpaid services.  

Most international credit cards are accepted in-store.  Online is a completely different system.