FBX export group instances to unity issue I have issues with exporting a group of meshes into unity.
I want to build a room in blender where the walls (img #1) are constructed separately and can be used as group instances in a new layer or scene (img #2).
All parts of a wall is parented under an empty. And so is the final room with the wall instances.

Problems occur when importing to unity, I select the walls (the group instances) in the room layer and tick "selected objects" and export.

Unity will import the three instances but with default position/rotation (img #3).

Also, when looking in the unity outliner, something seems off with the parent/child relations (img #4)

The goal is to export the room as is, like img #2.

Blender file:
You could try removing that empty object, in blender you use empty objects to avoid those z-axis issues between blender and unity. Also when exporting to FBX you could set what is your up-axis

EDITED:
From your shared file I exported one by one to FBX and them imported into Unity, without that axis issue, try that, BTW don't forget to set your forward and up axis... If it doesn't work let's go chat