Here is my guide on how to change the color of the aura effect of astral weapons, again its not on the dds.
What I did is make a trial & error and yes I manage to change the color of the aura effect of astral weapon.
In this screenshot the 3 highlighted value is the color aura effect, If I'm not mistaken you can't exceed more than 3 value for the color in hex.
Here is the hex value color for Crystal Green color "ABFAF2".
Here is the hex value color for Medium Purple color "8968CD"
Again, you need to do a "Trial & Error" for you to make it successful, and don't forget to backup your files.
R.E.S.P.E.C.T
Ragezone