Inspired by my older post about why wormwood speaks the way he does, I wanted to write something about WX and their emotions.
So like, wx goes on about how they don't feel emotions, even though they obviously do, but I don't think this is them being in denial, I think they just don't recognize their feelings as such
Being a machine they process things in a much much different way than a human would, so their thoughts and the way they experience things functions differently. You could couple this with their past life as a human, whatever distant memories they have of that time are the only things they can compare themselves to, and because they don't match up they conclude that they must not feel anything
Mostly I'm making this up as I go along but I have thought for a while that differences in computer and brain function changed them fundamentally into a different 'person', and was the cause for their negative reactions to the transfer.
For your Overlapped AU, do WX-78 and Wormwood still have the same way of talking as they do in canon?
Wormwood has a more coherent way of speaking, since here, he was actually compelled to learn fluent English. (Although he still struggles with certain words and in those instances, he does charades or mimics certain sounds)
While WX-78 or Woodrow, appears more calmer and distant, (still unprofessional) although that's just how they behave in a public setting. When left to their own devices or with people they can decently trust, WX-78 is much bolder, assertive and more expressive, as they are in canon.
Wormwood, in public is a very kind, considerate person, who is able to sway people with his manner and a sort of aura. While with the restaurant staff, he's much more awkward and clumsy, but still gracious, I guess this would be considered his true self.
And with his actual staff, he's cool and distant, similar to how WX-78 behaves in public, although he is much less aloof, rather solemn.