[SwedishHeat]

I'm trying to create a menu option that will show me TV shows and Movies side by side.

For example, if I have all Marvel Studios content in one folder, showing all MCU movies with the Disney+ shows. Is this possible? If so, how?

I've seen the wiki articles for custom universes and custom home items, but they require smart playlists that point to TV shows OR movies, it doesn't seem possible to do something with TV shows AND movies.

[Karellen]

I've seen the wiki articles for custom universes and custom home items, but they require smart playlists that point to TV shows OR movies, it doesn't seem possible to do something with TV shows AND movies.

Correct. You cannot combine tv shows and movies using smart playlists.

You can use a Basic Playlist, but this is a manual process and requires you to build the playlist item by item, rather than the automated way used by Smart Playlists.
Once you save the Basic Playlist, add it as a custom home item.
Use section 5 method... https://kodi.wiki/view/Basic_playlists