Im currently using Traditional ZH(HK) language setting, which uses the date display system as the (for lack of better words) “Chinese system”, where dates are listed like “6月19日, 週三”, however I would like to use the Seven Luminaries system (https://en.wikipedia.org/wiki/Names_of_the_days_of_the_week#East_Asian_tradition), available on the JP language setting, which displays date like “6月19日(水)”. I do not know Japanese but would like to use this date system whilst using Traditional ZH(HK) language setting. I have tried messing with settings in the Samsung Calendar app as well as messing with the settings of the phone itself but I cant figure it out.

I think I have done a pretty good job at describing what im asking about, but if not, I have also asked about it on Google support where I also included pictures: Change date display system on phone - Android Community (google.com)

Thanks for the help!