How to make semitransparency on an image plane of a 2D png in v2.8? I have checked past questions and this does not seem addressed. Blender 2.8.

How can I add additional transparency to a PNG imported as an Image Plane? E.g. make the entire picture half-transparent including it's normally non-transparent parts. For 2D images, I don't care about 3D at the moment.

Note I am not talking how to display existing alpha in a PNG, I know how that the Blend Mode needs to be set to Alpha for that for Eevee.

Also note that if it was a Reference Image, you can modify the alpha directly, but that does not show up in a render.

How to add additional transparency to a 2d Image Plane?

Thanks
Of course I figure it out right after asking, after a day of no progress.

To help the next person out:


Import your Image Plane
In Materials -> Settings -> Blend Mode and Shadow Mode select "Alpha Blend", this displays existing image transparency
Still in Materials -> Settings check Show Backface (important!)
In Materials -> Surface, add a new Shader, you can do this by clicking the white circle on the last existing shader, and select Principled BSDF
Switch to the Shading workspace, at the very top bar next to the Rendering tab you can access it from General under the + sign.
The Principled BSDF will already have an output to the Mix Shader. You need to connect the Colour output from the PNG to the Base Colour of the Principled BSDF.


Now you can modify the alpha in the Principled BSDF and it will show up in the image plane.

Hope this helps. This is not clear at all for beginners.