Exporting 3D objects with transparency I use Blender 2.82, and I use the principled B.S.D.F.
How do I export a 3D object with transparent textures? Like glass and stuff.
Making the obj, fbx, and files like that.
The rest of it works fine, like the lights, the height, normal map, textures, etc.

I look in the 3D viewer, there's no transparent textures.

What nodes I'm using in Blender


How the image looks in Blender


How the image looks in the 3D viewer
Use gltf/glb exporter to export with transparency .

The opacity alpha has to be in color image. (Check the documentation for correct export settings and node setup)

gltf format supports :


Color + alpha
Metallic + Roughness + AO 
Normal Map


all other maps will be ignored