Is ONE PIECE episode 882 filler?
Canon No, episode 882 of ONE PIECE is canon.
#882
The Paramount War! The Inherited Will of the King of the Pirates!
頂上戦争 継がれた海賊王の意思
Aired 28 Apr 2019
Mochibayo compiled this list from MyAnimeList's labels, because MyAnimeList's episode data is not reaching us at the moment.