Trilsettum Coronis Flower/Plant (No Ordinary Family)
Training Necklaces (Balala Fairies)
Moon Rings (Mako Mermaids)
First Prana (Sidekicks)
Training wands (Wizards of Waverly Place)
Ancient Urn (Charmed); contains the divine powers of godhood
The Ray Sphere (Infamous)
Devil Fruits (One Piece)
ÄRMs (Marchen Awakens Romance)
Camp Bloodbath (The Final Girls)
Butterfly/Moth Miraculous (Miraculous Ladybug)
Space-Time Feather (Valkyrie Crusade)
The twelve talismans (Jackie Chan Adventures).
The Bow and Arrows (JoJo's Bizarre Adventure)
Whitesnake's Stand Discs (Jojo's Bizarre Adventure)
Black Particles (Demashita! Powerpuff Girls Z)
Charlotte (Charlotte); gives random superpowers to teens/adolescents that wear out once they reach adulthood
Boosted Gear (Highschool DxD)
Philosopher's Stone (Arrowverse)
Moon Pool (H2O: Just Add Water/Mako Mermaids)
Ragtag (Static Shock) can give powers to others, but they are only temporary.
Upon arriving on Earth, Akuro (Alive: The Final Evolution) granted many humans special powers, at the cost of including suicidal urges that most find hard to resist.
The Darkness (Stupid Mario Brothers)
The First Evil (Buffy the Vampire Slayer) merges with Caleb to grant him superhuman strength and durability.
Mata Nui (Bionicle) gave his fellow Glatorian warriors elemental powers of fire, water, and wind
Kagura Tennōzu (Speed Grapher) carries a virus that can be transmitted to grant people's desires
Harimon (Krystalia) has the power to bestow powers to others using the power of his red stones.
While under a blue sun, Superman (DC Comics) develops "Superman Vision" that enables him to grant Kryptonian powers to others...
...as demonstrated here on Jonathan Kent.
When Alex (Misfits) took ecstasy, the powers he took will be given to the person he had sex with, similar to Seth, but, he gives all the powers he took away.
Mikan Sakura (Gakuen Alice) can insert Alices at will.
Cain (Supernatural) transfers the Mark of Cain to Dean Winchester, granting him Demonic Power Immunity and the power to wield the First Blade.
The Formula (Heroes)
Devil Fruits (One Piece)
Onomatopoeia's (Valkyrie Crusade) words can give power.
The Darkness (Skylanders) can grant dark powers to it's followers.
An Space-Time Feather (Valkyrie Crusade) can grant time-traveling powers.
With the power of the Butterfly/Moth Miraculous, Hawk Moth (Miraculous Ladybug) has the power to turn others into supervillains, bestowing on them an arsenal of unique superpowers.
Puppeteer (Miraculous Ladybug) is able to possess anyone who's doll she possesses. Should the doll be of a purified supervillain, they regain their villain identity along with their powers.
Him (Demashita! Powerpuff Girls Z) is able to create black dust, a mass of evil particles that are able to turn normal people or objects into supervillains, along with their own set of superpowers and persona.
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.
Each of the twelve talismans (Jackie Chan Adventures) grants the user a power stolen form the Noble Animals.
Ananke (The Wicked + The Divine) bestows onto others their godly identities, as well as all of their divine abilities.
Woden (The Wicked + The Divine) is able to bestow godly abilities to regular humans.
Cassandra Igarashi/Urdr (The Wicked + The Divine) was able to bestow her friends powers similar to herself along with a shared hive-mind, collectively becoming the Norns.
The Philosopher's Stone (Arrowverse) is a fragment of calcified speed force that grants superpowers to inactive metahumans across various timelines.