When I was transferring about three boxes of Pokemon from my Gen 6 and Gen 7 games to HOME, and it scanned my Pokedex, so I have my entire Gens 1-7 Dex completed in HOME. I know it scanned my Dex because it showed me the shiny Pokemon that I scanned QR codes for. I never had those shiny Pokemon. It did not transfer my Gen 8 dex when I deposited some of them into Pokemon Home. I'm confused. Is this supposed to happen?
When you open the Pokedex in Bank, it syncs the Pokemon you've seen and caught in the game you're using with Bank's Pokedex. When you transfer a Pokemon from Bank to Home, it also syncs your Bank Pokedex with Home's Pokedex. Home doesn't sync with LGPE or SWSH's Pokedex though, you have to deposit Pokemon from those games in Home to register their Pokedex entries, and Pokemon you've seen but not caught won't be registered.