>>50153308but you can get them for free
1. Download GO
2. Play until you get the Mystery Box and catch any mon you find
3. Transfer this mon to Pokemon HOME (be sure you linked your HOME account to GO beforehand)
4. Open the Mystery Box, catch a Meltan
4.5 Open HOME and receive the mon you transferred, then go back to GO and transfer Meltan to HOME
5. Open HOME, get your free G-Max Melmetal and pick the Meltan you had transferred
6. Move both of them to SwSh
No need for LGPE, no need to even pay for a HOME sub