Cosmetic System is a modular character system that combines various character parts in real time.
It supports multi-play and all features are available via Blueprints.
UE 5.4 Auto Generate Retargeter : https://youtu.be/eed8rKcA44Q?t=210
https://www.unrealengine.com/marketplace/en-US/product/cosmetic-system
Character Asset : https://youtu.be/ZOesJs8DWsA?si=vurqEr1HCM55vxbn