PNG-24 Exported Transparency Issue - Appearing to have a white matte?

[EthorTheGiant]

Hello all, I am working on a project and am running into some issues with exporting PNGs with transparency. I have never experienced this issue and am stumped.

The client reported that the PNG with transparency was looking way too light when used (they are using it as an asset in Unity on a game), so I investigated and it seems that when I copy and paste my PNG image into a photoshop document it appears very light, as if the PNG has a semi-transparent white matte behind it, this light version is what they see in their game. If I drag and drop the PNG image into a photoshop document, it creates a smart object layer and looks normal. 

I have verified color profile settings and played around with all of the settings in export and nothing seems to fix it.

Here is an export of a blank photoshop document with the PNG dropped in two ways. The top version is copy + pasted (this is what the client sees in their use), the bottom is smart object (or dragged and dropped in).

Any thoughts? Thanks in advance!

[S_Gans]

Hi. Can we please see your layers panel, at the time of the export? Specifically, the blending modes per layer - but all other info may be helpful in our ability to make suggestions...