hianime is the best site to watch I Got a Cheat Skill in Another World and Became Unrivaled in The Real World, Too: Real World SUB online, or you can even watch Isekai de Cheat Skill wo Te ni Shita Ore wa, Genjitsu Sekai wo mo Musou Suru: Level Up wa Jinsei wo Kaeta (TV Special) DUB in HD quality. You can also find Millepensee anime on hianime website.