Not gonna lie,
That actually sounds kinda cool. Camera pans around and you legit see the players on the title screen, moving, laying, etc.
Unless you were to film just that. Lol. It'll seem sort of lively.
Actually I heard there was a way to access Watermill. You have to open it in map maker, get a portal in, and export it and there ya go. That's what I've heard anyway. Whether it's true or not is a whole different story. And I don't think it would show other players in it in the title screen. Although in the old 1.13 map download, you are able to get into Watermill so it very well may be possible? I don't know, don't quote anything I say here it's probably wrong. Not experienced with maps at all. cx