evolution-plugins-experimental software package provides experimental plugins for Evolution, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install evolution-plugins-experimental
evolution-plugins-experimental is installed in your system.
Make ensure the evolution-plugins-experimental package were installed using the commands given below,
$ sudo dpkg-query -l | grep evolution-plugins-experimental*
You will get with evolution-plugins-experimental package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | GNOME |
| Package | evolution-plugins-experimental |
| Version | 3.22.1-2 |
| Description | experimental plugins for Evolution |
| Sub Section | gnome |