ffmpeg -i outlander_s03e06.mkv -ss 00:25:30 -t 180 -c:v libx264 -crf 18 -c:a aac precise_cut.mp4 Season 3 looks stunning, but your old tablet may choke on 10-bit HEVC. Convert to universal H.264 + AAC:
First, extract subtitles from your MKV:
Get-ChildItem "outlander_s03e*.mkv" | ForEach-Object ffmpeg -i $_.Name -c:v libx265 -crf 23 -c:a aac -b:a 96k "$($_.BaseName)_mobile.mp4" outlander s03 ffmpeg