Lunar Festival 2024 Vendor. Moonglade, with camps in ironforge, stormwind, darnassus, thunder bluff, orgrimmar, and the undercity. Before you use your lunar festival invitation (a reward from the previous quest) to teleport to moonglade and talk to valadar, make sure that you buy approximately 50 cluster rockets from the lunar festival vendor in your capital city (this is needed to summon omen later on).
You will need coins of ancestry to purchase them though. Join in the fun by dressing up in your lunar festival finery, launching fireworks, and paying homage to the elders throughout azeroth.