 There are three Pokemon you must trade to evolve in Pokemon Scarlet and Violet. The first one is Slowpoke. I caught mine at Kassaroya Lake. After that, go to Deli Bird Presence in Mesa Goza, buy a King's Rock and give it to Slowpoke to hold. Then trade it and you'll get a Slow King. The second Pokemon is Scyther. You can catch them in these locations. Go to Deli Bird in Levencia and buy a Metal Coat and give it to Scyther. Then just trade it to get Caesar. The final Pokemon is Haunter. I caught mine in this location. All you have to do is just trade it without an item to get Gengar. Make sure you are trading with someone you trust. Subscribe and tell someone-