I have physical games that are Japanese only regarding language support, if it’s a PS5 disc or Switch cartridge: the covers are of course written in Japanese & the region code for it is JPN (even if consoles are region free, why are language locks still a thing regarding the software as there’s no ENG?)
But, can you still trade them despite accepting this caveat: locked under a language barrier as the UI’s in game cannot be reverted to English. (Also, the classifications use CERO framework rather than ESRB). Like a CERO D (17才以上対象) is akin to a ESRB M17 & CERO C (15才以上対象) is similar to ESRB Teen.
Depends on the shop. You might also get a lot less for it, especially if it requires a region matching console; its going to sit on store shelves for a while, so the store owner might feel like the hassle isn’t worth the low cost unless its a rare game or something.