If I travel to Japan, can I buy genuine DVD? This is a coat CD. If you don't know what a coat is, please ignore it.

Yes, coat or AV, just put it in the checked baggage. You can't open the bag and check it.

In fact, the point is that DVD players sold in China are all over the country, and they can read Japanese discs.

For example, the original DVD player you bought in Japan can't read discs from other countries.