Create armature from MoCap position trajectories

Hi there,

I am trying to get an armature from MoCap trajectory data. So I was able to load in the position markers as empties and tried to rig the basic human armature of blender 2.8 to it. I had to adjust it manually and it is not perfect.
Now I want to animate the armature according to the marker positions. I tried copy constraints and track to constraints, but it resulted very bad.

Can someone please help?