““I love my brother Owen, though I do not know him,” sings Greta Kline on “Owen,” the first single from her forthcoming album as Frankie Cosmos, Zentropy, her first studio album with a backing band. The sentiment is endearing, but there is a sharp, grounded sadness to it as well—a recurring sentiment through Kline’s vast digital discography. Since 2009, the prolific young NYC songwriter has quietly”