How to use the Japanese version of Samsung in the country?

Cannot be used directly. Because Japanese servers are different from domestic servers, they need to be unlocked.

There are three major mobile phone operators in Japan (au, docomo, softbank). When the mobile phones of all brands of manufacturers arrive at them, their respective SIM cards are locked, and Japan does not sell bare phones, so this is the The company's mobile phone must be equipped with the company's card, otherwise it cannot be used in Japan.

Among the mobile phones of these three major operators, only 3-4 models of DOCOMO and 10-15 models of SOFTBANK can be used in China after being unlocked. Many places that sell mobile phones in China can unlock them. It costs about 100 yuan, but the operating language is still in Japanese, so you have to be mentally prepared. The only perfect mobile phone with Chinese language is the IPHONE, but the Japanese one also needs to be unlocked. Those with relevant knowledge can figure it out by themselves.