moviego VS editly

Github: https://github.com/mowshon/moviego (If you like the project, don't forget to give it a star)

Sounds like you already have a process for most of this, but I found https://github.com/mifi/editly to be incredibly helpful to run ffmpeg and make my little time lapse video. Could be useful for others

For example, this declarative video editor lib has JSON configurations for defining an output video:

Maybe this tool helps: https://github.com/mifi/editly

You seem to misunderstand what ffmpeg is for - namely the stream conversion of media. Only limited filters are available. You can write your own shaders and use cli tools like https://github.com/mifi/editly for automation surely

I used Editly to make a clip of several videos with transitions and screenshots. It worked out great with me just editing the json5 file to tweak things

https://github.com/mifi/editly (Node JS)

It's intended to work nicely with Editly, a CLI-based https://github.com/mifi/editly

The way I would do it would be using MoviePy (for Python). You may also have luck with editly (JavaScript). MoviePy has functions to create a TextClip, Images and overlays. It sure is possibly with ffmpeg filters - transparency mixing filters etc. yet you'd get faster results with modules like MoviePy / editly.