Could be both of them, they will fuse into one divine being. Now bear with me….
Davy Jones is an octopus in PoTC lore, and an octopus has 3 hearts. Blackbeard will become the new Davy Jones as he absorba Xebec and Imu to become a god — copied straight from the Bible. How? Possibly using the Personality Surgery via Ope Ope, he will get all 3 of their hearts and therefore their souls. Xebec’s heart is already inside Teach and that explains his atypical characteristics (never sleeps; can eat 2 dfs). The final heart is missing, and that final heart belongs to Imu — Davy Jones’ demon of a lover. She’s basically the equivalent of Calypso.
The 3 personas of God:
The Father — Xebec
The Son — Teach
The Holy Spirit — Imu