Getting Started - How to use the Mixamo Animation Retargeting plugin

1. Video tutorial
2. How to - step by step
   1. Enable the plugin
   2. Retarget a Mixamo skeleton to a UE5 character
   3. Next: retarget Mixamo and UE5 animations
3. What changed
4. IK, facial and other bones

Using the UE5 Mixamo Animation Retargeting plugin is very simple:

• ensure that the plugin is enabled (look under the Edit > Plugins menu);
• select a Mixamo skeleton asset and run the Retarget Mixamo Skeleton Asset contextual action.

You are now ready to retarget Mixamo and UE5 animations following the standard UE5 workflow (open the created IK Retargeter asset and use the export option on the desired animations).

Continue reading for detailed, step-by-step instructions.

Video tutorial

Look at the video tutorial below for a detailed, step-by-step guide on how to use the UE5 Mixamo Animation Retargeting plugin and how to easily retarget Mixamo and UE5 animations and chatacters in Unreal Engine 5. If you prefer a text version, continue reading below.

How to - step by step

Enable the plugin

Ensure that the plugin is enabled:

• open the Edit > Plugins menu;
• search for the "Mixamo Animation Retargeting 2" plugin name;

• flag the Enabled checkbox;

  

• restart the editor if asked.

Retarget a Mixamo skeleton to a UE5 character

The UE5 Mixamo Animation Retargeting plugin automatically creates all the required assets and configurations needed by the UE5 Animation Retargeting system of Unreal Engine 5 (IK Rig and IK Retargeter - an engine feature that allows animations to be reused between characters using different Skeleton assets).

Before using the plugin, ensure to have correctly imported your Mixamo characters and animations. Check the detailed tutorial on how to import a Mixamo character in your Unreal Engine 5 project.

To run the plugin on a Mixamo character:

• right-click on the Mixamo skeleton asset that you want to process;

• run the Retarget Mixamo Skeleton Asset contextual action;

  

  If the option is greyed out it means that the skeleton is not compatible with the Mixamo one (the bone names or their hierarchy are not matching the expected one). In this case, re-download your model from Mixamo and re-import it following the documentation.

• in the dialog that opens, select a supported target Unreal Engine 5 skeleton and then press the Select button.

  

  METAHUMAN: direct support for the MetaHuman skeleton (used also by the Manny and Quinn mannequins in UE5) is under active development and will be added in a future update. At the moment you can only select skeletons that are compatible with the classic and standard UE4 Mannequin. In the mean time, you can continue using the plugin to retarget Mixamo animations to a MetaHuman character following the instructions in the dedicated section.

Done :)

Next: retarget Mixamo and UE5 animations

You're now ready to retarget Mixamo animations to UE5 characters and retarget UE5 animations to your Mixamo character.

Check the documentation for more information, functionalities and tips on how to improve the final results.

What changed

Behind the scenes, with a few clicks the plugin performed all the following changes automatically:

• created one IK Rig asset for each of the involved Skeletons (IK_<Mixamo-Skeleton>, IK_<UE-Skeleton>), with the following features configured:
  • IK Retargeting chains;
  • Full Body IK solver (including goals and constraints).

  

• created a pair of IK Retargeter assets (RTG_<Mixamo-Skeleton>_<UE-Skeleton>, RTG_<UE-Skeleton>_<Mixamo-Skeleton>) to handle retargeting of animations between the involved Skeletons, with the following features configured:
  • Target IK Rig Asset;
  • Chain Mapping (including options);
  • for each Skeletal Mesh using the same skeleton of the Target IK Rig Asset:
    • computed an ad-hoc Retarget Pose (named after the target Skeletal Mesh), to perfectly match the target pose (this is essential for a correct retargeting);

    

• added a Root Bone to the Mixamo Skeleton (allowing to use Root Motion animations with your Mixamo character);

  

• configured the Translation Retargeting options (used when retargeting animations to another skeletal mesh using the same skeleton);
• configured a new Retarget Base Pose for the Mixamo character, with an A-pose perfectly matching the one of the selected UE5 Mannequin Skeleton (used by the LOD animation system);
• updated the Mixamo Character (i.e. its Skeletal Mesh asset) and all the associated Mixamo Animations in the project to account for the new Root Bone.

IK, facial and other bones

The plugin is able to retarget exclusively the known and matching bones existing in both the UE4 Mannequin skeleton and in the official Mixamo Skeleton LODs. Any bone not having a know counterpart on the other skeleton type, can't be retargeted. The reason is that the plugin has no information on their 3D transforms, as the matching bones simply don't exist in the other skeleton.

The plugin configures dedicated Full Body IK solvers for all the involved skeletons. In addition to improve the retargeting of animations, the exposed goals can also be used at run-time in custom Animation Blueprints and Control Rigs.