• Flowblade Editor - https://jliljebl.github.io/flowblade/
• Kdenlive - https://kdenlive.org/en/
• Shotcut - https://www.shotcut.org/
• Olive - https://www.olivevideoeditor.org/
• DaVinci Resolve - https://www.blackmagicdesign.com/products/davinciresolve/
• Blender - https://www.blender.org/
• OpenShot - https://www.openshot.org/
• LightWorks - https://lwks.com/
• HitFilm Express (not free)- https://fxhome.com/product/hitfilm-express
• Pitivi - https://www.pitivi.org/
• VidCutter (simple app) - https://github.com/ozmartian/vidcutter
• Cinelerra - https://www.cinelerra-gg.org/
• LiVES - http://lives-video.com/

Not a complete list but I wanted to get a few of these down on paper.

• Blender - http://blender.org
• Moho Animator - https://moho.lostmarble.com/
• Cavalry - https://cavalry.scenegroup.co/
• Toonboom Harmony - https://www.toonboom.com/products/harmony
• Cinema 4D - https://www.maxon.net/en/cinema-4d
• Pencil - https://www.pencil2d.org/
• Houdini - https://www.sidefx.com/products/houdini/
• Cartoon Animator - https://www.reallusion.com/cartoon-animator/default.html
• Stop Motion Studio - https://www.cateater.com/

• OBS - https://obsproject.com/
• onscreen graphics - https://h2r.graphics/
• screen cg - https://casparcg.com/ - https://github.com/casparcg/

• Avidemux - http://fixounet.free.fr/avidemux/
• MKV Toolnix - - https://mkvtoolnix.download/
• FFMPEG Batch - https://ffmpeg-batch.sourceforge.io/ - https://github.com/eibol/ffmpeg_batch
• MakeMKV - https://www.makemkv.com/
• Vidcoder - https://vidcoder.net/
• Handbrake - https://handbrake.fr/\
• Shutter Encoder - https://www.shutterencoder.com/en/
• Tricycle - https://github.com/kmcclive/tricycle
• WinFF - https://www.biggmatt.com/p/winff.html
• MPlayer (not really a converter?) - https://mplayerhq.hu/design7/info.html
• Mobile Media Converter - https://www.miksoft.net/mobileMediaConverter.php

You can create or edit subtitles. You can also use existing subtitle files, add them to the MKV video container (MKVtoolnix) and in doing that the video can have subs in different languages, or to get english subs for foreign movies. You can read SRT files in plaintext and you can actually edit styling in a code / text editor.

• Subtitle Edit - https://nikse.dk/SubtitleEdit/
• YIFY Subs - https://yifysubtitles.org/
• Open Subtitles - https://www.opensubtitles.org/en/search/subs

• Fre:ac - https://www.freac.org/
• Foobar2000 - https://www.foobar2000.org/
• Audacity - https://www.audacityteam.org/
• Clementine - https://www.clementine-player.org/
• Strawberry - Clementine fork - https://strawberrymusicplayer.org/
• CDex - https://cdex.mu/
• Mixxx - https://mixxx.org/
• QMMP - http://qmmp.ylsoftware.com/index.php
• Music Player Daemon MPD - https://www.musicpd.org/
• Amarok - https://amarok.kde.org/en
• Dopamine - http://www.digimezzo.com/software/dopamine/
• MPC-HC - No longer developed - https://mpc-hc.org/
• Audacious - https://audacious-media-player.org/
• Deadbeef - https://deadbeef.sourceforge.io/
• AIMP Player - https://www.aimp.ru/
• MusicBee - https://www.getmusicbee.com/
• MediaMonkey - https://www.mediamonkey.com/
• Quod Libet (linux) - https://quodlibet.readthedocs.io/en/latest/
• Foobnix - Linux - http://foobnix.com/en/index.html
• Odyssey (android) - https://github.com/gateship-one/odyssey/
• NextCloud Player - https://rello.github.io/audioplayer/
• Plexamp - https://www.plex.tv/plex-labs/
• Famistudio Chiptune Editor - https://famistudio.org/
• Zrythm - https://www.zrythm.org/en/

• VideoJS - https://videojs.com/
• PLYR - https://plyr.io/ - plus lightbox for it - https://github.com/biati-digital/glightbox
• MediaElementJS - http://www.mediaelementjs.com/
• JPlayer - http://jplayer.org/
• JWPlayer - https://www.jwplayer.com/
• Able Player - https://ableplayer.github.io/ableplayer/demos/
• Paypal Accessible Video Player - https://github.com/paypal/accessible-html5-video-player
• Kaltura (old) - https://developer.kaltura.com/

• MetaX - https://danhinsley.com/
• MP4 Video & Audio Tag Editor - https://www.microsoft.com/en-us/p/mp4-video-audio-tag-editor/9nqxzbd9kxmf