Hi MRZylinder,
Due to it’s translucency, in order to have a transparent material appear the same on both sides you will need to have 2 planes instead of 1 with the UVs facing the viewer from each side (as shown in the images below.) Furthermore, it would be more efficient to import one window then place multiple instances of that window.
You can only render two sides of a plane if the material is opaque as shown below:
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