Correct way to transfer movies from iTunes to newer TV app?

I just updated from a 2018 intel MBP to an M2 MBP and used apples migration assistant to transfer all my content. The 2018 mac was rarely updated and was running macOS Mojave and iTunes. Only on upgrading to the M2 running macOS Sonoma did I discover iTunes is defunct and Music and TV apps have replaced it, but I'm not sure the right way to transfer my own digital Movies library and I'm experiencing a slight issue.

I opened the TV app for the first time and my entire list of Movies with the cover art was immediately there. My iTunes movie library was located on an external hard drive that was connected, but movies wouldn't play, so I went to TV in the menu bar and clicked: Settings/Files and changed the 'TV Media folder location' so it pointed to: HD2/iTunes/Movies

That worked and movies would play, but each time I access a movie file in the TV app a subfolder titled 'Movies' is created within my original 'Movies' folder and the movie file is transferred to that brand new subfolder: HD2/iTunes/Movies/Movies

Only the .mv4 movie file is transferred though. Any subtitles files or any other associated files remain behind in the original folder, so the data is split up.

Is there a way to stop this happening so the new TV app just uses the original string and keeps it as it was, or alternatively transfers all my movies INCLUDING the subtitle files to a new folder on my external hard drive?

Grateful for all help provided.