The art kinda reminds me of Dark Cloud...but, that's likely not it.
The game's main character, shown at the event in silhouette form, will be voiced by Marina Inoue. She delivered a video message at the event. In attendance at the event next to Okamura was voice actress Mariya Ise. She will have the role of the main character's sister. The sister relationship will be a major part of the game.
The theme of the new Atelier game is "The Promise Begins." There are many meanings to this theme. Explained Okamura, these include "The promise between the main character and her sister, and the promise that the developers will offer something interesting to the players."
Looks like I got the translation right.