https://gematsu.com/2018/09/castlev...e-night-rondo-of-blood-rated-for-ps4-in-korea
The Korean Game Rating Board has rated Castlevania Requiem: Symphony of the Night & Rondo of Blood for PlayStation 4 (Japanese, English).
While Castlevania publisher Konami has yet to announce such a title, it sounds like a collection including the 1997-released Castlevania: Symphony of the Night and 1993-released Castlevania: Rondo of Blood.