Alex (Misfits) gained the power to remove a person's power through sexual intercourse after having a lung transplant from the previous owner of the power.
Penny (Charmed) with the power stripping potion.
Mikan Sakura (Gakuen Alice) can permanently steal an Alice at will or by accident.
Tommy Clark (Heroes Reborn) erases Hiro's power just by being held by him
Aang (Avatar: The Last Airbender) use Energybending to eliminate one's bending abilities.
Amon (Avatar: The Legend of Korra) can use Bloodbending to sever the connection between a bender and their bending abilities by disrupting their chi paths.
Enrico Pucci's Stand, Whitesnake (Jojo's Bizarre Adventure) can remove the Stands of others, storing them in discs. It also makes it able to bestowal these Stands upon others by inserting the discs on them.
Through a contract, Hades (Disney's Hercules) erases Hercules' superhuman strength.