Create the jail
Install the encoding options you'd like to use inside the jail. 'jls' to see the list of jails and to enter the jail: 'jexec #'.
I installed the following
pkg install python
pkg install ffmpeg
pkg install handbrake
Filebot: Extracted the portable package into a folder in the jail -- Screenshot
pkg install libass
portsnap fetch
cd /usr/ports/audio/lame
make install clean (just keep hitting enter till it's finished)
Make sure the jail can access your encoding / media folder(s)
I used this python script and commented out import ntfsutils.junction (Line 63)
and then changed these lines:
FFMPEG = '/usr/local/bin/ffmpeg' #'/usr/bin/FFMPEG'
HANDBRAKE = "/usr/local/bin/HandBrakeCLI" #'/usr/bin/HandBrakeCLI"
FILEBOT = '/filebot/filebot.sh'
Run the Python Script in the jail:
root@encoder_jail: nohup python scripts/conv2mp4.py
Thanks to @KameeCoding & https://www.reddit.com/user/infinull for helping me getting it working.