What you are interrested in is Add suppport for link types, and if you want it usable in built-in obsidian views, it should probably be added as a core feature and not a plugin.
Just using notes meta-data won’t solve your usecase since even if you have #people tags on the persons notes, it’s the link itself between the movie and the person who has to clarify the relation between those two, not the nature of the person.