GET A SPECIAL MELMETAL IN POKÉMON HOME
If you send a Pokémon to Pokémon HOME from Pokémon GO, you’ll receive the Mythical Pokémon Melmetal as a Mystery Gift in Pokémon HOME. This Melmetal is a special one that hasn’t been available before—this Melmetal can Gigantamax in any battle in Pokémon Sword and Pokémon Shield that allows it, such as a Max Raid Battle!
Please be aware that Pokémon HOME Mystery Gifts are only available on the mobile device version of Pokémon HOME, and the ability to connect to Pokémon Sword and Pokémon Shield is available only on the Nintendo Switch version of Pokémon HOME. Also note that you cannot feed Melmetal the Max Soup from The Isle of Armor, the first wave of content for the Pokémon Sword Expansion Pass and Pokémon Shield Expansion Pass. Depending on your OS or device, you may not be able to use certain features.
They are slowing allowing more people to connect with Home, currently need to be level
30 24 21 12 or above in Go.
Just did it and it worked for me.