"The Voidstorm" is the beam assaulting the Sunwell until [spoiler]. The world from which it originates, and where the Devouring Host is based, is called that as well in the game, but a side quest reveals the original name of this planet: Predacea.
This addon aims to replace many mentions of "[the] Voidstorm" as a zone name with that actual name. Basically, it establishes the headcanon that the Azerothians learn that name shortly after arriving there, and use it instead of "The Voidstorm".
The name is masked in quest titles and texts, names and tooltips of items/spells/achievements, zone transitions, as well as map markers for e.g. portals and the mouseover name on the Quel'Thalas map. The text on the actual map texture will not change - am investigating whether it's possible to replace that with a shopped texture.
Due to certain values being secret in combat, the terms "Voidstorm" may still appear, e.g. in tooltips.

If you find or think of more instances that should be replaced, let me know! In particular, there may be more quests where "Voidstorm" is only mentioned in the Progress/Completion texts, you can't search for that on Wowhead, found one example, but there may be more.

Everything should work in other locales (client languages) but there may be jank as I only speak English and German well, took other languages from Wowhead. Confident that the Romance Languages are handled ok, but absolutely no guarantee for languages using other alphabets. Currently, I don't know what Predecea is called/spelled in the Chinese cn/tw locales, as Wowhead doesn't have the "Completion" text for the quest Sifting Through Void where the name "Predacea" is revealed (the name is also stated in chat while doing the quest) so I'm using the Latin-character "Predacea" for now. If someone gives me the term as used in the cn/tw clients, I'll add that.
Please do report issues with syntax, context etc. wherever you see them!

Some Addons are hooked as well, wherever they display the zone name, or quest texts:

DialogueUI
Immersion
Storyline
Classic Quest Log
SexyMap
WorldQuestTracker
Interactive Wormholes

Suggest ones you use here, too!

Alas, Predacea