Hello. Is there anywhere I can find pose libraries (preferably free) that define some (common) motions of this or that (also provided) rigged/animation-ready character? Or for one of the ubiquitous ones like Ludwig? Or is there a preferred way to create, edit and share common motions (walking, running, etc)
Thanks!
i dont know about premade pose libraries but theres no reason why you couldnt reuse them 
just have to make sure that the armature is setup the same (with the same names) so the actions have something to relate/ reference
It sounds to me like you may be thinking about mocap libraries. Blender does support them and there literally thousands of motions available for a blender rig. Just Google “blender mocap” or Blender Motion Capture" and prepare to be overwhelmed.
Sorry so long to reply. Was overwhelmed. Yep, it’s always the right keyword that’s needed. You’ve certainly opened that door. Thanks.