Cavia (Drakengard and BulletWitch) made Nier. Feelplus (N3 II: Ninety-Nine Nights and Lost Odyssey) are working on Mindjack. Even The 3rd Birthday has outside help from Hexadrive, the studio behind Rez HD.
Lord of Arcana, though, is being made inside Square Enix. “It’s an in-house dev’d game,” Rob Rutter, Brand Manager, said in the comments section of the PlayStation Blog.