Complex sentence: For this album, Seohyun took full initiatives and control of the production process, shaping her own musical style--a fulfillment to what she was unable to do previously being in a larger musical group.
Split into simpler sentences: For this album, Seohyun took full initiatives and control of the production process, shaping her musical styles. She described it as an opportunity to convey her own message, something that she was unable to do fully being in a larger musical group.