Game Freak pushed out a server-side fix for Pokémon Home earlier today to finally address a bug that involved missing challenges in some players’ games.
Additionally, Game Freak has fixed the issue revolving around the Magearna that was only unlocked for players who completed the full Pokédex. Now, players can unlock the special Pokémon by completing a full National Pokédex instead, which means you’ll have to catch a lot less Pokémon to get your hands on one.
For instance, if you have all original 151 Pokémon in Home and complete the Kanto Pokédex, it should unlock Magearna for you moving forward. The same can be said if you complete the Johto, Hoenn, or other regional Pokédex.
This Magearna has been illuding players for some time since it was added to the game. The Pokémon arrives in your box once you unlock it with the ability Soul-Heart and is level 50. It knows the moves Fleur Cannon, Flash Cannon, Defense Curl, and Rest and will always be Mind natured.