- I can't see Chromie but everyone else can
- Chromie isn't here to give me a daily quest in Mechagon
Chromie is one of the visitors who appear randomly in Mechagon to provide daily quests. Visitors in Mechagon are visible for a full day, and then replaced with a new visitor the next day.
To see which visitors are active you can check fansites that track Mechagon visitors. For example: Wowhead lists the active Mechagon visitors on their front page here in the "Today in WoW" section.
Note: Chromie will not appear for characters who have completed the Introductory questline for Mechagon in the same daily cycle. If this is the case for you, your character will see her the next time she appears.