Access to the "locale" Attribute of OD Core

Problem(s in general): Weekday / Work week /Week of year troubles of the date-time spark functions.

Wish: An instance wide solution.

Derived question:
Is there a way to gain access/manipulate the “locale” Property of the OD Core?
Is the OD Core written in Java? (I know from experience that the Java standard API for Time-/zones does work well even for odd edge cases.)
Would/Do the spark functions inherit the “locale” attribute?