This makes absolutely no sense to me…but I fixed it!
After flipping through various screens and settings, I went into the actual texture for itself, the Albedo layer.
My decals consist of an Albedo and a Opacity texture.
The solution that removed the horrible white edging was as follows:
- Open the Albedo texture
- Navigate the Details panel
- Adjustments
- Set Brightness from 1.0 to 0.0
This process resulted in the texture for the Albedo going pitch black, but as seen in engine the decal on the signpost is very much still there with no white edging!
Before:
After:
Hope this solution can help anyone else that may come across this during gamedev!