Dynamic bone
https://www.youtube.com/watch?v=GXrllGsGlFI
VRChatでは揺れものをつかうときにDynamic boneを使うのが一般的だったが、最近はPhysBonesを公式が実装しており、将来的にDynamic boneのサポートを打ち切ると明言されている Avatar Dynamics is also significantly more performant than Dynamic Bones. That means more frames for PC users – and the ability for Quest users to finally see their friends’ hair, ears, and clothes move with real-time physics! Likewise, while support for Dynamic Bones will be going away in the future
チュートリアル
https://booth.pximg.net/116d9118-2beb-4b74-8d60-47ab67429662/i/1823194/674463e7-35af-4922-8a85-fa7624471c64_base_resized.jpg
DynamicBone設定支援ツール