redk5 wrote:Too bad I don’t have Pokémon Let’s Go and now I’ve missed the opportunity
No missed opportunity!
You can still get Meltan from the Let's Go games, perhaps you know someone with a Switch and the game? That would be enough.
If that does not work out, one of the big research quest lines has a Meltan as a reward.
Last but not least, when they allow Pokémon Home (mobile app) to be able to function with Pokémon GO, you can receive the Meltan box through that by just sending a Pokémon off to Pokémon Home. It's a useless app if you don't have a Switch right now, but it will be good for Meltan boxes. This is a feature yet to come and I highly recommend my favourite source LeekDuck for all the newest data.

Cause they only talk about stuff that is 100% to be in the game, no data mined assumptions.