If it is enough to schedule the objects relative position to the project origin, then you can make a simple object to solve the problem. Simply add 3 parameters, for example xPos, yPos, zPos, then add the following 3 lines to the parameter script:
parameters xPos = SYMB_POS_X
parameters yPos = SYMB_POS_Y
parameters zPos = SYMB_POS_Z
You can make a simple 2d representation for this object, place it, and then you can list these 3 parameters if you make your own schedule for that.
If you need world coordinates, then there is no proper solution for that in GDL, please check GDL-Related Changes in ARCHICAD 19.
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