Re: Which version of Riku became a Xehanort vessel?
The line he says in the trailer is not indicative of Data-Riku's personality (he's even more stoic than the real Riku[seriously watch how he reacts to Chip & Dale panicking]) whatsoever, imo. I would personally say that it's definitely Repliku for a few reasons:
Firstly, the data blocks were briefly shown to be coming from the dark Beymax during the on rails section (while your riding Beymax). It was brief, and easy to miss, but definitely still there. They also behave similarly to microbots, as well being comparable in size to them. This coupled with the fact that one of the dark Beymax's hands is made up of something similar (Both in the trailer & the concept art), makes this the most likely scenario in my mind.
Secondly, the line "we're always trying to one up each other", sounds similar to things Repliku said when he had is memories jacked. His non serious smile also implies the whole situation was (at least to him) nothing but a competition between him and Sora. It's also quite a coincidence that the ones who made the decision to meddle with his memories in the first place are also norted alongside him (i.e. Larxene; Vexen).
Thirdly, we see Siax... bafflingly approach Lea a top the Twilight Town clock tower of all places. If there's even the slightest chance that they have a semi- peaceful or positive conversation (where they reminisce; comfort each other; make some secret plan; etc.) then you can make a pretty strong argument for Repliku and Riku doing the same thing, potentially to an even greater extent.
Fourthly, the data scape was rendered within the computer of Disney Castle which (edit: unlike Ansem's computers) is incapable of materializing any form of code (though Riku can pull you into it and send you out of it, there's no indication he could do this to himself). After Maleficent specifically infiltrated Disney Castle for the sole purpose of obtaining the journals, I'm pretty confident they would be well guarded. And before you say, "Maleficent getting in was a one time thing due to Xehanort's revival, now they can just rely on the Cornerstone of Light to keep the darkness away," please explain how that wouldn't also keep Xehanort away? He has an even stronger connection to the darkness than Maleficent and would likely have just as much trouble. Not to mention no one knows where the journals that render the Datascape are kept in the first place, or else Maleficent would never have held Minnie hostage to get to it.
As for his eyes, I'd imagine it's a similar thing to Marluxia's initial reveal (remember we only saw Repliku in one other trailer one time).
Anyways, that's my two cent. I personally hope it's not Data- Riku though, i just can't see him behaving this way, especially after the many, MANY things he said and did regarding the threat of the bugs during Re: coded (he was filled with journal's data for a reason yall). I'd also love for it NOT to be Repliku either, but if I had to chose.....
