Legato does.
Both internal and external LWS that have the Legato plugin applied.
The main advantage is that all poses and animations are easy accessed for review & selection because the library is stored in the negative frame range. The marker/regions provide the "library index" for identification.
Together with frame range selection they are often step #1 in many Legato functions.
Markers and regions utilize retime/clone/transfer/reverse/mirror/bake/hold/lock/etc, a PoseType track per character, 7 TextTracks (for lipsync, directing, mood, pov, ...).
Some utilities like organize schematics, animated render region (also frame split for distributed rendering), and Genoma rig renaming (esp. their master channels) to have more than 1 rig in a scene. Also new: switch backplates by pressing selector button: low/mid/highres.
Legato processes hierarchy items of a hierarchy master including related (pole/goal/etc) items, filtered by tool channels, item locks, item visibility, and booleans for genus/morphchannels/masterchannels. Hierarchy masters are easy to reset to another body part so you´re able to transfer poses/animations on a sub-selection of your rig. Alternatively it supports processing by (multi genus) groups.
Unfortunately it's in transition for features/fixes anno 2020, unless LW2020 doesn't support LScript anymore.
I also need to check LW2019 LWS file format compatibility in case of a Transfer from an external reference.
Those are the reasons it's not public at the moment.
Not enough spare time is another reason.
Read some details on this old web page:
http://home.kpn.nl/vincentmesman/tools/legato.html
Some features are unfinished/broken/untested (after some upgrades and changes).
Legato is functional and improved in many ways but not really ready for wide spread release and support.
I could make a quick video to show some features that are actually functional.
Let me know if you're interested in a download link.