elpa-powerline software package provides Emacs version of the Vim powerline, 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 elpa-powerline
elpa-powerline is installed in your system.
Make ensure the elpa-powerline package were installed using the commands given below,
$ sudo dpkg-query -l | grep elpa-powerline *
You will get with elpa-powerline package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Lisp |
| Package | elpa-powerline |
| Version | 2.4-1 |
| Description | Emacs version of the Vim powerline |
| Sub Section | Lisp |