In a Marker: you would have to modify the GDL Script of the Window Marker object to be able to do that.
Label: yes, you can display that info in a Label.
For ARCHICAD 18, see this series of posts:
http://archicad-talk.graphisoft.com/viewtopic.php?p=233623#233623
It talks about mapping IFC Properties to an Object parameter (in your example, it will be the Glazing Area parameter), then shows how to display that IFC Property in the Generic Label 18.
In ARCHICAD 19, you have to use the Tags and Categories Label 19 instead of the Generic Label but the steps are the same.
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