Arena Trap (Doubles encounter rates)
Compound Eyes (Chance of wild Pokemon holding item is doubled)
Cute Charm (66.7% chance that wild encounters will be opposite gender to the Pokemon that has Cute Charm)
Flame Body (Egg hatching takes half as long)
Flash Fire (50% chance encounters will be Fire-type Pokemon)
Harvest (50% chance encounters will be Grass-type Pokemon
Honey Gather (Honey may be picked up at the end of a battle)
Hustle (50% chance wild Pokemon will have the higher levels possible in their range)
Hyper Cutter (In Emerald only, if a Hyper Cutter Pokemon uses Cut in the overworld, some tall grass will be removed)
Illuminate (Wild encounter rate increases by 100%)
Immunity (Gens 3 and 4 only, Pokemon with this Ability won't take Poison damage in the overworld)
Infiltrator (Wild Pokemon are less likely to appear)
Intimidate (If a Pokémon with Intimidate is in the first place in the party [even if fainted], there is a 50% chance it will prevent a random wild encounter that would have occurred if the wild Pokémon would be at least 5 levels lower than the Pokémon with Intimidate.
Keen Eye (Same effect as Intimidate)
Lightning Rod (In Pokémon Emerald, Trainers registered with the PokéNav's Match Call function will call twice as often if a Pokémon with Lightningrod is in the first place in the party (even if fainted).
In Pokémon Sword and Shield, if a Pokémon with Lightning Rod is in the first place in the party, there is a 50% chance the game will force an encounter with an Electric-type Pokémon, if one is possible.
Magma Armor (Same effect as Flame Body)
Magnet Pull (50% chance game will force a Steel type encounter, if possible)
No Guard (Same effect as Arena Trap)
Pickup (Pokemon can find items if they don't have one already)
Pressure (Same effect as Hustle)
Quick Feet (Wild Pokemon encounter chance is decreased by 50%)
Sand Veil (If in Sandstorm, encounter rate is decreased by 50%)
Snow Cloak (If in Hail, encounter rate is decreased by 50%)
Static (Same effect as Lightning Rod)
Steam Engine (Same effect as Flame Body)
Stench (Same effect as Quick Feet)
Sticky Hold (Bites occur more often while fishing)
Storm Drain (50% chance of Water type encounter)
Suction Cups (Same effect as Sticky Hold)
Super Luck (Same effect as Compound Eyes)
Swarm (In Emerald, cries are heard more frequently)
Synchronize (Pokemon have the same Nature as Pokemon with this Ability)
Vital Spirit (Same effect as Pressure)
White Smoke (Same effect as Quick Feet)
Source
Hope I helped!
