The 5 strongest pokémon you can use to beat espurr are:

Espurr type. Damage (and dps) is 20% higher than the standart as the pokémon and the move have the same type. Espurr is the pokemon whish has one type ( psychic) from the 6 generation. You need to know your pokemon's exact level.

Though espurr’s expression never changes, behind that blank stare is an intense struggle to contain its devastating psychic power. You can find it in such biomes as a forest, a forest hills and others. Lampent is a tier 1 raid boss in pokémon go and is a part of the halloween mischief event part 1:

Though espurr's expression never changes, behind that blank stare is an intense struggle to contain its devastating psychic power. The user turns the ground into electric terrain for five turns. Espurr is a psychic type pokémon, which makes it weak against bug, ghost and dark moves.

It evolves into meowstic starting at level 25. Evolves into meowstic at 25 level. This pokemon's accuracy can't be lowered by others;

It evolves into meowstic upon reaching level 25.