Recently hear of one such promising project, called "HEAT", but it feels like non-legit and feels like "ready-to-run-with-your-money" vibe, but seems already integrated with UnrealEngine METAHUMANS according to their documentation: https://docs.heat.tech/blender-plugin/get-started
I apologize if this is not the place to ask for addons/plugins, but I have a strong feeling that there is some long time ago established asset-system or marketplace for animation/posing assets I just have not heard of
Thank you all in advance