PNG to DDS (Issues)

Hey fellas,

Hoping someone with more expertise can help me out here.
I've been using the in-game texture cooker to convert from PNG to DDS however I am encountering some transparency/colour anomalies when doing so.

I actually thought I fixed this issue when I spent considerable time on the matter yesterday yet here we are.

Pictured below is the textures in PNG
Looking carefully you will see there is a silver etching to the edges of the ladder and jerrycan holder here as well as a grungy texture on the top roof tent in the second image.


The following images are the exact same textures after being cooked to DDS
The silver edges & grunge are gone and the overall colour is slightly darker.
(The etching is still visible on the parts in the normal map but the colour is gone.)


I've posted here as I'm by no means an expert with this stuff and am assuming I am making a rookie mistake somewhere along my process.

My substance painter export details are:
PBR Metallic Roughness - 8bit color - no padding (passthrough)

Cheers in advance.