What is the best eevee evolution to use against lance?

The best Eeveelution to use against Lance in Pokémon is Jolteon. Lance specializes in Dragon-type Pokémon, which are weak to Electric-type attacks. Jolteon, with its high Special Attack and Electric-type moves, can deal significant damage to Lance's team. Additionally, Jolteon's speed allows it to outspeed many of Lance's Pokémon, giving it an advantage in battle. Other Eeveelutions like Vaporeon or Umbreon may be less effective against Lance's Dragon-type team due to their type disadvantage.