The following passage is from this answer quoted from Agni Purana
An anuloma marriage is a marriage where the husband is from a higher class than the wife. The offspring of such a marriage belong to the mother’s class. A pratiloma marriage is a marriage where the wife is from a higher class than the husband. Chandalas were born this way from brahmana women, Sutas from kshatriya women, Devalas from vaishya women, Pukkashas from kshatriya women and Magadhas from vaishya women. Chandalas are executioners, Sutas charioteers, Devalas guards, Pukkashas hunters and Magadhas bards. Chandalas should live outside the villages and should not touch those belonging to any other class.
The passage clearly says that Chandalas are born due to pratiloma marriage by a Brahmana woman. A Brahmana woman can marry only a Brahmana man according to the scriptures.
But, is a Chandala born if, a Brahmana woman marries a man of any other varna? Or does it happen only if the Brahmana woman marries a Sudra man?
Are there any explicit mentions about the (classification or charactersitcs of) offsprings born of a Brahmana woman and a Sudra man?