https://plugins.b2evolution.net/ldap-plugin

We updated the plugin to make it work with b2evolution v6 (which has enhanced encryption for passwords).
The latest version (for b2evolution v6) is available at: https://github.com/b2evolution/ldap_plugin

https://b2evolution.net/man/?s=ldap&submit=Go&disp=search

And it works. I know because we have several clients using b2evo on an intranet with LDAP.