1. Here's a great tip that I thought of and actually tested out. Google Chrome has a built in Live Caption feature. So for any videos that don't have subtitles I open the video in Google Chrome - quickest way is to drag the video to Google Chrome and it will open in Chrome then Chrome will auto transcribe the video for you!
You must enable Live Caption in Google Chrome settings to do this >
Click on the 3 dots menu top right, then in the search at the top search for Captions then switch on Live Captions.
2. The only downside with Chrome is there are no keyboard shortcuts for videos except Space bar start/stop but I figured out how to get keyboard shortcuts working using a Chrome extension. Video Speed controller is the extension and you have to enable the option for external URLs. You have to setup the shortcuts in the Options in the extensions. Also you MUST go to Chrome Settings > More Tools > Extensions > Video Speed Controller and click on Details then enable "Access to File URLs"
You can generate captions and send them to Google to translate videos, podcasts, games, live streams, video calls or other audio media from Chrome Browser. Turn Live Caption on or off The audio and
support.google.com
3. If you need to record the live captions I got you for that too

type this in to the URL box > chrome://accessibility/ then at the bottom is a list of open tabs click on start recording. Then when the video has stopped click stop recording and there will be a big load of text scroll down and the whole transcribed text will be in that text list
Live Caption I thought of the rest of it I thought of but needed to browse Reddit etc to figure out how to get everything working, so props to Redditors etc who provided the rest of the info.
So now with the above system I have a way of Auto Transcribing videos using Chrome so you get live subtitles on the video as you watch. I have a way of using keyboard shortcuts to skip back and forward. I have a way of saving the text of the Live Caption transcription. Awesome!
TL;DR
1. Use Google Chrome Live Caption feature to auto transcribe subtitles
2. Use Video Speed controller to setup keyboard shortcuts if you want them to navigate videos (you can just use the mouse as normal if u don't need keyboard shortcuts)
3. Use chrome://accessibility to access Start Recording option for the tab that is playing the video and the Live Caption text will be recording in that text data which you can copy, that's if you also want a text copy of the transcription.