Navigate to the encounter and item settings. While the standard randomizer can randomize wild encounters, advanced versions or companion tools like Save Game Editors (e.g., PKHeX) allow you to inject literal eggs directly into your PC boxes. Inject Eggs via PKHeX:
Technically, yes. You would need to breed eggs in another game, trade them over to your Emerald cartridge via a link cable, and then abide by Egglocke rules manually. However, this is cumbersome and slower than using an emulator. Pokemon Emerald Egglocke Rom Download Gba
In a randomizer, you see the broken Pokémon immediately. In an Egglocke, you spend 10 minutes biking up and down Mauville City's cycling road, waiting for an egg to hatch. The suspense is physical. When that egg cracks open to reveal a at Watson's gym, you will actually cheer. When it reveals a Sunkern before Flannery, you will feel true despair. Navigate to the encounter and item settings