Start with a local question. Keep the network, language, and delivery settings separate so the result tells you something useful.
Keep Japanese market inputs explicit
For Japan testing, record ja-JP, JST, JPY when those are the settings your application uses, and distinguish them from the proxy's observed country. A Japanese page may also reflect account, delivery, or browser preferences. Change one input per comparison so the result remains explainable.
Exercise Japanese address and text variants
Use a Japan test address you control to inspect prefecture, postal code, building fields, and any kana requirements. Compare full-width and half-width input only as separate cases. A working Japanese route cannot fill those fields or prove that checkout accepts the customer's address.
A Japan proxy is not a buying service
Databay's Japan route is not a shopping or forwarding agent. It does not purchase goods, receive parcels, or supply a local account. For permitted storefront research, verify the same seller, variant, yen amount, and delivery conditions before comparing results across countries.