There are several moves that will change the enemy's ability:
- Gatro Acid: suppresses an enemy's ability (the enemy basically has no ability while this is in effect)
- Worry Seed: changes the enemy's ability to Insomnia
- Skill Swap: swaps the user's and target's abilities
- Entrainment: gives the target the user's ability
- Simple Beam: changes the enemy's ability to Simple
There is only one ability that will change the enemy's ability:
- Mummy: any Pokemon that makes contact with the Pokemon with Mummy will have their own ability changed to Mummy.
There are a couple of abilities that will ignore some enemy abilities, however, if that counts:
- Mold Breaker
Where this becomes harder is the part concerning items. The ability Klutz will make the user be unaffected by their own held item, which is the closest I could think of a Pokemon ignoring items. I am not sure there is any move or ability that lets the Pokemon ignore their enemy's held item, however.