Norse
Njörðr
sea, wind, wealth
Celtic (Irish) tradition. See the whole pantheon.

The Boyne rose when she went to the well of wisdom and its waters burst out, mutilating her. In another tale she and the Dagda are the parents of Aengus.
Deities in other traditions who share a theme with Boann: sea and waters. This is overlap in one area only.
Norse
sea, wind, wealth
Norse
the sea, brewer of the gods' ale
Norse
drowning, the sea's net
Egyptian
the primeval waters
Egyptian
Nile, fertility, kingship
Mesopotamian
the primeval sea, mother of the gods
Mesopotamian
fresh water below the earth
Mesopotamian
salt water, primordial mother