Sakura's Eevee was revealed to have evolved into Espeon at some point between Trouble's Brewing and Espeon, Not Included.
In Pokémon Heroes: Latios & Latias, an Espeon was Annie's main Pokémon. It would use its Psychic to incapacitate foes.
In The Saffron Con, Lilian Meridian used an Espeon to test the stage's lighting effects. Before the Saffron City Contest, it performed an appeal which entranced May's Squirtle.
In Second Time's the Charm, Anabel used an Espeon as the third and final Pokémon during her rematch against Ash in the Battle Tower. It was eventually defeated by Pikachu's Volt Tackle.
Virgil's male Vaporeon debuted in Team Eevee and the Pokémon Rescue Squad!, along with an Eevee and her other evolutions at the time. He reappeared in Lost at the League! and A Unova League Evolution!, and in a flashback in Curtain Up, Unova League!.
In Eevee & Friends, a vain Espeon was with an Eevee and its other evolved forms, including the newly introduced Sylveon. It despises getting messy in any way.
In Master Class Choices!, Amelia used an Espeon alongside a Dragonair in the Fleurrh City Showcase. Together, they made it past the Theme Performance. However, they came in second during the Freestyle Performance, losing to Serena and her Braixen, Pancham, and Sylveon.
In Turning Heads and Training Hard!, a Trainer's Espeon was summoned to help Ilima's Eevee perform Extreme Evoboost. In the Poké Problem segment of the next episode, it saw Ilima and Eevee off.
In Johto Photo Finish, Gary's demonstration featured an Espeon evolving from an Eevee.
In A Bite to Remember, Brock's demonstration featured a Vaporeon evolving from an Eevee.
A Coordinator's Espeon appeared in Pros and Con Artists.
An Espeon appeared in Destiny Deoxys, under the ownership of a Lady.
A Coordinator's Espeon appeared in Mean With Envy.
In Hi Ho Silver Wind! and Deceit and Assist, a Coordinator's Espeon competed in the Hoenn Grand Festival.
A Coordinator's Espeon appeared in The Saffron Con.
In May, We Harley Drew'd Ya!, a Coordinator's Espeon competed in the Kanto Grand Festival.
In Not on MY Watch Ya Don't!, an Espeon was hypnotized by Psyduck.
In Giratina and the Sky Warrior, an Espeon was together with an Eevee and the other six Eeveelutions at the time.
In Tag Team Battle Inspiration!, Serena's fantasy featured an Espeon as she imagined what her Eevee could evolve into.
In Racing to a Big Event!, a Trainer's Espeon competed in the Pokémon Pancake Race.
Two Trainers' Espeon appeared in The Power of Us.
A Trainer's Espeon appeared in Turning the Other Mask!.
A Trainer's Espeon appeared in Imitation Is the Sincerest Form of Strategy!.
In Battling on the Wing!, a Trainer's Espeon watched the battles during the Manalo Conference.
A Trainer's Espeon appeared in Exhibition Unmasked!, Fiery Surprises!, and From Z to Shining Z!.
In JN049, an Espeon was at the Eevee Evolution Laboratory.
||Espeon, the Sun Pokémon. Espeon are able to read air currents, allowing it to predict the future, as well as its opponents' next moves.
||Espeon, the Sun Pokémon. It uses the fine hairs that cover its body to sense air currents and predict an opponent's movement.
||Espeon, the Sun Pokémon. It predicts opponent's moves and detects air currents with its body hairs.
- Eevee cannot evolve into Espeon or Umbreon in FireRed and LeafGreen due to the lack of a time system. In order to be obtained and added to the Pokédex in these versions, an Eevee must be traded to Ruby, Sapphire, and Emerald Versions, evolved there, and then traded back, or else traded from Pokémon Colosseum or Pokémon XD.
- Espeon shares its category with Sunflora and Volcarona. They are all known as the Sun Pokémon.
- It also shares its category with Solgaleo in Japanese, as Solgaleo is also known as the Sun Pokémon in that language.
- Espeon was designed by Atsuko Nishida.
- Espeon has blue inner ears in the games, but in other forms of media, such as the anime, they are often purple.
- Espeon is tied with Glaceon for the highest base Special Attack stat of all Eeveelutions.
Because of its feline appearance, Espeon appears to be based on the legend of the bakeneko and the nekomata, both magical cat yōkai described as mysterious and intelligent, but the distinction between the two is that the latter is depicted with a forked tail. It may also be based on the Lynx (mythology), a feline creature that possesses the psychic power of clairvoyance. The red coloring of the jewel could be a reference to a lunar eclipse, an event in which the moon passes directly behind Earth and into its shadow, making it appear red in color.
Its large ears can be traced from various felines such as caracals, oriental shorthairs, lynxes, and possibly servals. Espeon's ability to sense minute shifts in the air with its sensitive fur mirrors a cat's ability to use its sensitive whiskers to detect the slightest directional change in a breeze.
Espeon is a combination of ESP (a branch of psychic abilities) and eon (an immeasurably long period of time, possibly referring to how long evolution takes naturally). Eon is a suffix all Eevee evolutions share and was Eevee's English prototype name.
Eifie is a combination of エスパー esupaa (ESPer, a person with psychic powers) and フィール fiiru (feel), referring to its extraordinary sensory abilities. It is very similar to Eevee, in both writing and sound (イーブイ/エーフィ).