Yep, there are two on the Wyrmrest Community Project Discord calendar (invite: https://discord.gg/wrawcp/ | https://discord.wrawcp.info/). They are:
Hallow’s End Costume Party
Time: 6 PM ST
Where: Darkshire, Duskwood
Faction: Neutral
Hosted by: Rhoiene
Come for the treats, stay for the costume party. The small hamlet in the haunted woods is having a costume party with food, candies, and a competition for the most impressive costumes.
Hallow’s End Tarot Card Reading
Time: 8:45 PM ST
Where: Whitegrove Chapel, Drustvar
Faction: Neutral
Hosted by: Kalimeris
Drop by to have your character’s tarot card read by Mavvi Solarvale.
There’s also the ongoing Haunting of Hallow’s End hosted by Kirsy: