Notes: Lurantis is an unusual choice for a Defogger due to Contrary with the addition of Leaf Storm and Superpower to hit Sap Sipper users.
Leaf Storm is Lurantis's primary STAB despite coming off a lower base special attack due to the boosting affect of contrary, making it the stronger option compared to its other Grass STAB. Leaf Storm is your secondart slash due to the increased critical rate which Petal Blizzard does not have while being able to capitalize on Superpower's boost and Lurantis's higher base attack.
Superpower allows you to 2hko Sap Sipper users including Zebstrika and Bouffalant and provides a way to deter Defiant users such as Pawniard and Purugly.
This EV spread allows Lurantis to always avoid the 2hko from lead golem's (Jolly) Stone Edge after leftovers,survive Life Orb Zebstrika's Overheat after Stealth Rocks, and outpace Assault Vest Bouffalant.
Synthesis provides helpful recovery to allow it to defog more consistently.