This plugin is called pylsp_black and it's also the name that pylsp uses to load it:

INFO - pylsp.config.config - Loaded pylsp plugin pylsp_black from <module 'pylsp_black.plugin' from '/Users/rafal/Library/Caches/Sublime Text/Package Storage/LSP-pylsp/lib/python3.10/site-packages/pylsp_black/plugin.py'>

The settings it provides use a black key though. This is problematic because that means that the pylsp.plugins.black.enabled key doesn't work and pylsp expects pylsp.plugins.pylsp_black.enabled instead.

All configuration keys other than enabled work as expected because pylsp uses different code path for reading those.