Axel and Lexa

Axel & Lexa (ゴールドだのシルバー, Gōrudo dano Shirubā) are the fraternal twin Gym Leaders of Gardenia Town's Pokémon Gym. If beaten, they will reward a trainer with the Stinger Badge. They both specialize in Normal-type Pokémon.

On the wiki
Axel and Lexa are fraternal twins, Axel being a boy and Lexa being a girl, who inherited the Gardenia Town Gym from their father. They are the weakest of all eight Gym Leaders in Hora, being the first badge a trainer will receive if they are beaten. They both will battle the trainer opponent at the same time, being the only Gym where the Gym Leader battle is a double battle.

While Axel's Zangoose uses primarily Normal and Fighting-type moves, making it easy for a Pokémon with any fighting moves of its own to defeat it, such as the Herracross from Illusion Forest, Lexa's Snorlax uses an assortment of element moves, making the challenge much more difficult.