I have several videos I need to process using avisynth then encode to hevc mkv format.
I can use avsproxy and open in avidemux but I can't batch it. I have a lot of videos that use basically the same script. I can easily create a script for each file but I don't have anything that takes it as an input.
If Windows is an option, you can use FFASTrans - it's automation encoding software, based on AviSynth and FFMpeg.
You can either use built-in modules to process video or your own AVS files as a source of video.
The software is freeware, though is not open sourced.