Can Blackbeard end up being an ally?

Just a thought I had while thinking if Nightmare Luffy may make a come back during the Final War...

The only DF I remember to control souls is that of Gecko Moria, whose DF seems to have been taken by Blackbeard if I'm not wrong. (I might be wrong about this, but bear with me for a minute)

So anyways, if during the final war Blackbeard makes an appearance and asks whoever is using Moria's DF to extract all the souls of the people who died during the war and shove them in Luffy. Luffy runs from it but Blackbeard nullifies)stops him somehow and forces the souls inside him, bringing back the long-feared Evil-version of Nika.

Blackbeard is doing all that he's doing is to become a Celestial Dragon and get a chance to do what 'someone else' couldn't

Luffy wants to be the King of the Pirates and the Seas, while Blackbeard wants to replace Imu and rule the world like 'someone' desired.

I don't think Luffy knows or blames Blackbeard for anything that has happened until now, including Ace's death. And he's still unaware of what has happened with Coby and Garp.

(Hopefully this gets approved and I hear your views)