Invoking systemd-doc-directives opens man page for systemd.directives, which contains a list of directives. But I can't figure out how to jump to a man page of a particular directive.
At the moment, that's all it does. It would be nice to make it smarter, but it probably means parsing systemd.directives.7.gz (instead of the man buffer output) for it to not be awful.
Invoking
systemd-doc-directives
opens man page for systemd.directives, which contains a list of directives. But I can't figure out how to jump to a man page of a particular directive.