Yes an extension maybe, I'll make the movie metadata spec public as soon as I get some time, it should be easy to make an IMDb extension or a tmdb extension from there.

Also you can filter those out completely cause they'll be in no one's web of trust.

Yes. Although I was thinking in something simpler: exporting to a file from IMDb and importing to nostr from that file (creating, signing and publishing nostr events to several relays). 🫂