Pokémon Let’s Go Pikachu and Let’s Go Eevee mod: Alternate Trade Evolutions (Lv50 version) by Dio Vento
This mod will allow Kadabra, Haunter, Graveler (and Alolan Graveler), Machoke, and Meltan to evolve into their final forms at Lv50.
It does not remove the ability to evolve them by trade.
Pokémon evolved in this manner will flag as “hacked” until they have been traded once. Melmetal evolved in this manner might flag as “hacked”.
Put the Atmosphere folder on the root of your SD and then boot the game normally while running Atmosphere CFW, the mod should load silently and seamlessly.
v2 – added Alolan Graveler
v3 – added Meltan