So you’ve created the SOFFIT model with the camera set to the standard Left view.
Notice the upper left corner and the orientation of the axes.
And your REFLECTED CLGS file is created using the Standard Top view. (top left corner and axis orientation.)
When you copy the geometry from the SOFFIT SKP into the REFLECTED CLGS file, it will come in with its orientation matching the axes of the REFLECTED CLGS file.
The easy fix would be to either rotate the pasted geometry or rotate the geometry in the SOFFIT file so it is oriented to allow the Top view to be used instead of the Left side view.
If you are going to continue making these 2D models in SketchUp, I would suggest that you set up your default template so the camera is set to Parallel Projection and the standard Top view. Then all of your models will be drawn in the same orientation.
Here I’ve rotated the geometry so it can be seen from the Top view.
Then I copied it and pasted it into the other file and you can see it is properly aligned for the Top view.