The RTC Widget is like a software version of an RTC module… it is NOT a clock face it is a placeholder in the App that indicates the presence of that server based timekeeping function, and is used for setting the required timezone of the users phone (when traveling).
As per the code you pasted here, the actual time/date format is coded in your sketch and send back to Display Widgets, etc, in digital format only… there is NO analog format for the App.