Dude, I HIGHLY DOUBT IT. Oda is going to give Teach some weird upgrade and make him consume Imu's soul.
If Teach absorbs them, Imu will literally just take over. Imu is 800 years plus old MINIMUM.
Even if Xebec is secretly controlling his own son / had his soul implanted into him? Xebec, nor Teach, are gonna do shit to Imu.
It is time to stop the delusions. Teach and his daddy are not connected to the ancient past like Imu. Teach, if Imu and their power even ARE devil fruit related? Have had 800 years plus to master their abilities, and said abilities are better and more crazy than both the darkness and quake fruit.
Oda would NEVER have Luffy fight a half-baked nerfed Imu-fied Blackbeard who can barely use the Devil devil fruit or whatever Imu would have. Same reason why all those "Blackbeard will steal Kaidos fruit" theories were dumb. Oda wont re-use villain powers like this. Nor will he throw away the whole build up of Imu and the Wolrd Govenrment all for some Pirate. Again, this is NIKA PIECE okay? Teach will be the obstacle Luffy has to beat to GET the One Piece.
You know, the last lore drop before the final war. There is no scenario where Blackbeard somehow is the FINAL villain. His dream is bullshit. The world would never submit to some fat Pirate nobody. His own crew does not love him nor respect him. They dont even fear him.
His fate is to be like his daddy. Betrayed by his crew of cowards and opportunists, his dreams dashed. He can be a great, perhaps even THE best villa in One Piece has ever had for all I care. But he aint stronger than Imu, nor is he gonna be the FINAL villain of this story.