

There are also non-english language public trackers that don’t leverage western style filename rules.
E.g. mazepa.to (Ukrainian) and rutracker.org (russian). The sites require registration (open to all), but the torrents are public (no ratio requirements and torrents do not have the private flag).
The search functions support English language titles with no issues at all. You can find any mainstream movie/show on both trackers. Rutracker has some niche content that I’ve not been able to find on specialized private trackers.
One drawback is that the trackers require local language dubs/VO, so some some content is never released on them.
Handbrake is designed for CPU based transcoding. You want slow CPU based encoding for archival storage.
You can mux into MKV via MKVtoolmix (available on all major platforms/linux distributions). You encode video via the x264 and x265 codecs, while I use handbrake, I do believe there are many other frontends that likely allow you to switch to GPU encode.