During Wikimania Learning Days I saw that the Programs & Events Dashboard could highlight the editions an user has made inside an article as a way to show the Diff. The button says "Authorship highlighting" and it is explained here: https://wikiedu.org/blog/2017/04/19/authorship-highlighting/
It uses wikiwho and whocolor... but it seem that is only availabe in English. Could it be installed in other languages? It would be an awesome way for teachers all around the world to evaluate student's work.