The single biggest reason a downloaded English audio track "doesn't work" is .
Downloading audio tracks for copyrighted movies falls into a legal gray area similar to downloading movies.
Once you have a source file with English audio, use this tool to extract the .ac3 or .dts audio track from the container. Making the Audio Track Work: Syncing and Merging
This comprehensive guide explains exactly how to find, download, and sync English audio tracks for your favorite movies using currently working methods. Understanding Movie Audio Files
When you buy or rent a movie digitally, the English audio is included. You don’t download it separately.
Set it as the if you want it to play automatically. Click Start multiplexing at the bottom.
, you will see both the original video/audio and your new audio. Uncheck the original audio if you only want the English one, or keep both. Set the Language for the English track to "eng".
Some subtitle communities, like OpenSubtitles or local language forums, maintain sub-forums or Discord servers where users share audio tracks to help international viewers synchronize English audio with local video releases. How to Play Movies with an External Audio Track