The calendars of many people in different parts of the world are local and specific to those places. Is it possible to personalize the course calendar and change it to Chinese/Hijri(my case)/etc? For a functional localization, it is necessary to convert all dates to the local/national calendar used by the user.
If you are asking “(e.g.) what is a Hijiri calendar”, It’s a local calendar in use in most of Arabic countries. You can take a look at conversion here: Hijri to Gregorian Date Converter - Islamic Date Converter | IslamicFinder
For example, 4 Nov 2020 should be 18 Rabi-ul-Awal 1442 (indeed in arabic words: ۱۸, ربيعالاول ,۱۴۴۲)
samples:
https://u.teknik.io/mH2fQ.jpeg
https://u.teknik.io/mPZHU.png
https://u.teknik.io/MxpWa.png