Hey Minato! Great to hear from you.
I remember having issues in UE3 with Japanese keyboards where you couldn’t open the long console with the “全角／半角” key (the key that is in the same place that the “~” key is on an English keyboard), but tab worked to open the short console.
I asked Rob and Jun from the Yokohama office, and they said that the “@” key opens both consoles (long and short) for them on their Japanese keyboards. I think they are using regular UE4 though, and not Rocket, but I think it’s the same in both. Does that work for you?
Perhaps the Editor team could make the key used to open the console rebind-able by the users, I’ll see if that’s an easy change to make.