Hello,
You can export animations as fbx and you can import it to Blender without any issues. But you may use some plugins for animation controllers for Mannequin.
Viewing post in Unreal Engine Sex Animation Starter Pack comments
Hello , thank you so much! I really glad you like the animations.
The fbx has root bone and optimised for unrealengine by using control rig of unreal engine. I haven't tested with Unity.
About the commissions , i would love to make but currently i am working on a game and it consumes all the time i have :(
Please let me know if i can help you about the Unity pipeline.
Best Regards