、。
She was not only an actress but also a famous painter.
Literal
She [topic-は] actress is [not only-ばかりでなく], famous painter also was.
~ばかりでなく presents the first quality (being an actress) as already established, then adds a surprising second quality (being a famous painter). The でもあった combines も (also) with あった (was) — literally 'was also.' The slightly formal であるばかりでなく gives this sentence a written or biographical register, appropriate for describing a notable figure's accomplishments. A more casual version would use ~だけでなく.