teamteam321 If your atlas is in the newer atlas format, it will have pma: true in the atlas file and the unpacker will perform unpremultiply alpha. If you have older atlas files, you can probably edit them to add the pma: true field.
The following thread may be helpful for you:
https://esotericsoftware.com/forum/d/24261-how-to-cancel-the-premultiplied-alpha-when-unpacking-the-cli/9