Renim Node was a promising node-based Retargeting addon. Unfortunately the development seems to have halted around Blender 2.91. The addon is unlikely to work with the latest versions of Blender.
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ReNim - Node-Based Retarget Animation
ReNim Node Blender add-on allow you to retarget any animation to bone or bone control. Very good for retarget any motion capture animation to any rig. No worry about bone orientation and scale. The purpose is to retarget animation and clean up action with NLA Editor Show Case Tutorial (Maybe ?) Current Version : 0.1.0 [02/11/20] Feature Mapping bone on the fly. Easy tweak. Preset. Bake animation. Origin Retarget system originally from my previous project Blende...
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