Using Japanese characters in Menubar date/time

I used to be able to set the Menubar date/time to Japanese and the Gregorian calendar (e.g., using the Japanese character for days of week and am/pm), configuring it via the Date/Time panel in Settings, while still using English as my primary language. I'm on Big Sur now and it doesn't seem like it's possible to configure this anymore - even if I choose Japanese calendar, it still uses English for the date/time. Is there a way to do this anymore? Thanks!