Found this on another forum post from 2018 and I was wondering if that market has evolved and if anything better has been released since.
From this list I only tried MKVCutter which seems broken and SolveigMM which works but isn't freeware and the interface is clunky.
I've stumbled on Lossless Cut https://github.com/mifi/lossless-cut/
Unfortunately the app doesn't work as advertised, at least not in an intuitive way. No matter how I do my cuts or modify the export settings, I'm never getting the cut on the actual selected key frame. Funny thing is when selecting "chapters only" in the export window, it'll create chapters based on your actual cuts. I've processed the output file through my mkvmerge script
Code:
"C:\Program Files\MKVToolNix\mkvmerge.exe" -o "!outputDir!!fileName!.mkv" --split chapters:all "!episodeFile!"
and it successfully separated all my chapters in individual mkv files like I would have expected Lossless Cut to do.
Although this workaround is working, the "smart cut" function of Lossless Cut didn't work for me.
I would like to share an example but I'm not sure if this is authorized here since it's copyrighted content I got from a streaming service using widevine. In the meantime here's the MediaInfo of my file.
Any help is welcomed