Animation Poses and Mirror

Could we have the simple ability to create save animation poses to a pose library tab similar to Motionbuilder.
And have the ability to also mirror those poses and copy & paste them within the timeline.

This simple feature would go a long way to being able to create walk cycles and many animations Directly in UE4, without the need for external programs.

I m looking for the way to do this,but donot find any. Its any way have been find? :sweat_smile: