Thanks to a new feature PyPI - Versions from Framework Classifiers on shields.io, It is now possible to include a badge displaying the supported Plone versions of your add-on.
[![PyPI - Plone Versions](https://img.shields.io/pypi/frameworkversions/plone/pas.plugins.authomatic)](https://pypi.org/project/pas.plugins.authomatic/)
We already have this applied to pas.plugins.authomatic and to kitconcept.contentcreator.