In MicroStation V8i and later releases that support geographic coordinate systems there are key-in commands available to manage coordinate system definitions.
geocoordinate assign <gcsname>
Assigns a geographic coordinate system to the active model.
geocoordinate assign reproject <gcsname>
Reprojects design file graphics in the active model from the current geographic coordinate system to a new geographic coordinate system.
Deletes the current geographic coordinate system assignment
Where <gcsname> is the coordinate system name displayed in the Geographic Coordinate System dialog.
Example: geocoordinate assign wi-s
These key-in commands can be used with the MicroStation Batch Process utility to assign, reproject, or delete geographic coordinate systems on a group of files in batch mode.