The latest One UI 7 beta brings a new toggle that lets you add media controls to the notification shade in the new split ...

You may have to turn off settings that make media players ask to ... It will list all possible video or audio player. Select VLC, and video files will instantly change icons to VLC.

That's why one of the first settings I enable on my new Windows ... Another default app I like to change is the media player. I prefer using a VLC media player because it's far more versatile ...