ZenTools

ZenTools extracts cooked packages (.uasset/.uexp) from the IoStore container files (.ucas/.utoc + .pak).

Works on all versions of UE4 that have IO Store.

Usage:

"ZenTools ExtractPackages <ContainerFolderPath> <ExtractionDir> [-EncryptionKeys=<KeyFile>] [-PackageFilter=<Package/Path/Filter>]

If your game has encrypted paks, you must provide a keys.json, in the following format:

{
  "KeyGUID1": "KeyHex1",
  "KeyGUID2": "KeyHex2"
}

Obviously if your game only has one encryption key, you only need to specify one entry.

Example:

ZenTools.exe ExtractPackages "D:\SteamLibrary\steamapps\ccommon\somegame\projectname\Content\Paks" "D:\somegame\Output" -EncryptionKeys="D:\somegame\keys.json" -PackageFilter=/Game/Path/

Since the game in the above example needs an AES key, this is the following keys.json file:

{
  "00000000-0000-0000-0000-000000000000": "DEADBEEFCAFEDEADBEEFCAFEDEADBEEFCAFEDEADBEEFCAFEDEADBEEFCAFEDEAD"
}