More realistic Wonder Trade

[Rangi42]

Based on https://www.wondertradeanalytics.com/:

• 5% held item
• 1/1024 Pokérus
• 10% cumulative perfect IVs
• 1/1024 shiny
• 20% random Egg move
• +5% Hidden Ability
• Gradually increasing chance to force an early-game Pokémon, reset daily (Magikarp, Pidgey, Hoothoot, Rattata, Sentret, Caterpie, Weedle, Ledyba, Spinarak, Sunkern, Ditto)
• Moderately increased chance of an early-game Pokémon if that's what you're trading (stacks with the daily increased chance)

[Rangi42]

If you trade an Egg, you should likewise receive an Egg.