During the Games, Elesa is seen with a total of nine Pokemon. All of the Pokemon she chooses to battle with are Electric, and some of them have other Types associated with them as well. Therefore, Elesa really does stick to her word of loving Electric Type Pokemon. Five of the Nine are just Electric, one is Electric/Flying, two are Bug/Electric, and one is Ground/Electric. I noticed that during multiple battles, Elesa will use the same Pokemon twice. This happens with Emolga and with Galvantula. That must mean she really loves those two Pokemon! (They are going to be listed in Alphabetical Order):

Her Anime party consists of three total Pokemon. Ash comes to the battle with just one Pokemon, Palpitoad, thinking that he would be able to win due to a Type advantage. Elesa, slightly offended, knocks out Palpitoad in the second round. The battle is paused so that Ash can go and get more Pokemon to battle with. Elesa also calls her Tynamo Electric Queen, during the anime as well, which confuses Ash because of it's fish appearance. (They are going to be listed in Alphabetical Order):

Elesa makes a debut in Pokemon Generations during the thirteenth episode. She comes in to help defeat Team Plasma with the other Gym Leader's in her region. Elesa's only known Pokemon so far is Zebstrika. This special episode shows how well Zebstrika and Elesa have a bond due to the fact that she was able to ride on him as they were running through the battle field, attacking. This will be updated if Elesa appears again in any further episodes.

In the Pocket Monsters BW manga, the only known party member is Emolga. Elesa is the fourth Gym Leader that Red encounters, and we see Emolga standing close to Elesa at all times.

However, the Pokemon Adventure manga party consists of four total Pokemon. Elesa had a Blitzle since childhood that later in the manga series evolves into a Zebstrika. She also has two Emolga in her party that represent a male and female Emolga. One of the Emolga's was used to battle against Black.