If we all want to help PR get integrated, please go leave a comment in the PR comment thread(it’s’s Pull Request) The more attention it gets in there the more likely we’ll get some news on integration.
In the meantime,
Nate provided 4.9 and 4.10 back-ports for us to use’s shading model. (not a plugin, requires source build)
Nate’s post
[EDIT]
Started a Feature Request thread in feedback section for’s Toon Shading Model PR
Link to thread