bochs-sdl software package provides SDL plugin for Bochs, 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 bochs-sdl
bochs-sdl is installed in your system.
Make ensure the bochs-sdl package were installed using the commands given below,
$ sudo dpkg-query -l | grep bochs-sdl *
You will get with bochs-sdl package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Other OSs and file systems |
| Package | bochs-sdl |
| Version | 2.6-5 |
| Description | SDL plugin for Bochs |
| Sub Section | Otherosfs |