Replacing the voice acting in the video?

Question

PHP

There is a video, you need to do the following
1 - take out the sound that is already embedded in the sound file, separate the video and sound and make connections.
For example, the video is in English, the sound is taken out to the English voice acting so that it would be possible to switch the voice acting.
2 - select the voice acting and play from the moment where the voice acting was replaced.
This must be done using php, without local download. That is to press the button to process video, and the server will divide a sound. Will render and make a connection between video and voice acting.
Although I also considered another option, load another video with a different voice acting and naturally play back from the moment when the sound was changed. True, in this version, if the video weighs 1 GB, and 4 voice acting, then this is already 4 GB on the server will be occupied, which is irrational in terms of resources. After all, the voice acting itself will weigh up to 100 MB per 1 GB.
video format - mp4 (only mp4)
https://videojs.com/ - video player
ui - vue.js
back - symfony

Answer 1

Why take it out? This is how video containers support multi-channel. Yes, and in the docks for your player it is: https://docs.videojs.com/tutorial-audio-tracks.html