You can set the language in the right top cog and then settings, but I don't recall if there's "Japanese" language there...
So if it's set to Japanese, it might be a different infotainment system. There is the NAC_EUR, used in Europe and all over the World, but there's also the NAC_CN, used in China - in the Peugeot 4008, somewhat a 3008 XL version. I don't know if that version is also used in Japan and if it has the English language.