This Blender addon allows you to import and export meshes and animations to and from the PSK and PSA file formats used in many versions of the Unreal Engine.

This software is licensed under the GPLv3 license.

Features

• Full PSK/PSA import and export capabilities.
• Non-standard file section data is supported for import only (vertex normals, extra UV channels, vertex colors, shape keys).
• Fine-grained PSA sequence importing for efficient workflow when working with large PSA files.
• PSA sequence metadata (e.g., frame rate) is preserved on import, allowing this data to be reused on export.
• Specific bone collections can be excluded from PSK/PSA export (useful for excluding non-contributing bones such as IK controllers).
• PSA sequences can be exported directly from actions or delineated using a scene's timeline markers, pose markers, or NLA track strips, allowing direct use of the NLA when creating sequences.
• Manual re-ordering of material slots when exporting multiple mesh objects.

Installation

For Blender 4.2 and higher, it is recommended to download the latest version from the Blender Extensions platform.

For Blender 4.1 and lower, you can install the addon manually by following these steps:

1. Download the .zip file of the latest compatible version for your Blender version (see Legacy Compatibility).
2. Open Blender.
3. Navigate to the Blender Preferences (Edit > Preferences).
4. Select the Add-ons tab.
5. Click the Install... button.
6. Select the .zip file that you downloaded earlier and click Install Add-on.
7. Enable the newly added Import-Export: PSK/PSA Importer/Exporter addon.

Legacy Compatibility

Below is a table of the latest addon versions that are compatible with older versions of Blender. These versions are no longer maintained and may contain bugs that have been fixed in newer versions. It is recommended to use the latest version of the addon for the best experience.

Critical bug fixes may be issued for legacy addon versions that are under Blender's LTS maintenance period. Once the LTS period has ended, legacy addon versions will no longer be supported by the maintainers of this repository, although the releases will still be available for download.

Blender Version	Addon Version	Long Term Support
4.1	7.0.0	No
4.0	6.2.1	No
3.4 - 3.6	5.0.6	June 2025
2.93 - 3.3	4.3.0	September 2024

Usage

Exporting a PSK

1. Select the mesh objects you wish to export.
2. Navigate to File > Export > Unreal PSK (.psk).
3. Enter the file name and click Export.

Importing a PSK/PSKX

1. Navigate to File > Import > Unreal PSK (.psk/.pskx).
2. Select the PSK file you want to import and click Import.

Exporting a PSA

1. Select the armature objects you wish to export.
2. Navigate to File > Export > Unreal PSA (.psa).
3. Enter the file name and click Export.

Importing a PSA

1. Select an armature that you want import animations for.
2. Navigate to File > Import > Unreal PSA (.psa).
3. Select the PSA file you want to import.
4. Select the sequences that you want to import and click Import.

Note that in order to see the imported actions applied to your armature, you must use the Dope Sheet or Nonlinear Animation editors.

FAQ

Why can't I see the animations imported from my PSA?

Simply importing an animation into the scene will not automatically apply the action to the armature. This is in part because a PSA can have multiple sequences imported from it, and also that it's generally bad form for importers to modify the scene when they don't need to.

The PSA importer creates Actions for each of the selected sequences in the PSA. These actions can be applied to your armature via the Action Editor or NLA Editor.

Why are the mesh normals not accurate when importing a PSK extracted from UE Viewer?

If preserving the mesh normals of models is important for your workflow, it is not recommended to export PSK files from UE Viewer. This is because UE Viewer makes no attempt to reconstruct the original smoothing groups. As a result, the normals of imported PSK files will be incorrect when imported into Blender and will need to be manually fixed.

As a workaround, it is recommended to export glTF meshes out of UE Viewer instead, since the glTF format has support for explicit normals and UE Viewer can correctly preserve the mesh normals on export. Note, however, that the imported glTF armature may have it's bones oriented incorrectly when imported into Blender. To mitigate this, you can combine the armature of PSK and the mesh of the glTF for best results.

There is also an open pull request to add support for exporting explicit normals from UE Viewer in the future: https://github.com/gildor2/UEViewer/pull/277.