Some have already compared Zoey to Quinn in terms of personality, and you can agree with that when you look at Zoey from detention, where the MC meets her. Zoey from Interlude has spent more time with the MC, and if there's one thing we know about the MC, it's that it can influence people in a positive way.
Very interesting observation
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Zoey is technically the girl that the MC has spent the most time 'with', although she didn't think it was an actual relationship and he did somehow (it never came up I guess
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). It's possible that the Zoey we see in the Interlude is very different from the Zoey in the past who was acting out a lot and ended up in detention, and that her change is due to the MC's influence. We already know Zoey influenced the MC to a large degree, so it makes sense, although again she only thought of him as a 'best friend' so maybe the change wasn't as drastic.
The interesting part of this is the fact that we actually get to change Zoey's personality based on the choices we make during the Interlude - could this be the in-game representation of what you're talking about? In other words, are we the players choosing how Zoey acts, or are we choosing how the MC has influenced her to act? For example, we can choose for Zoey to act more like a DIK, is that because she's naturally a DIK or because that's how the MC liked her to act? It's interesting because we don't get the choice to do this with any other character in the game, besides the MC himself, and as you point out Zoey is the character who has spent the most time with the MC.
If the choices we make for Zoey are in fact representing how the MC has influenced her, it would be quite a clever narrative tool by DPC to show the effect he has on people he's with.
Or all of this is wrong and I'm over-analyzing a normal game mechanic, but hey it's 6 months until the next episode so what else do I have to do
As far as Zoey's personality compared to Quinn's, it's hard to say, but we've obviously seen both of them change in the MC's company. I could easily over-analyze everything we do know but no one's interested in that, so I'll try and make an interesting observation myself instead. Here we go
Zoey's reaction to Neil at the end of episode 8 - the big beautiful smile - is the same reaction that I envisioned Quinn eventually having to him. Some of the scenes I'm most looking forward to in Quinn's story are her meeting with Neil and bonding with the MC over their mutual love of their dads. Quinn's a daddy's girl, and the MC loves his dad a lot too, so it's something they share in common, along with growing up poor. Neil is the kind of dad who would accept girls like Quinn and Zoey unconditionally as part of the family when the MC brings them home, and that kind of acceptance for a girl without a father figure around would be met with a lot of hesitance at first, but once they're comfortable with it, they'd embrace it completely. So Quinn and Zoey are somewhat similar in that aspect of their personalities I feel, at least Zoey of the past - surprisingly, despite the way episode 8 ended, Zoey gets no interaction with Neil in the Interlude, but then she has limited interaction with the MC too once she makes the decision to leave. Regardless, it's interesting to think of the current Zoey as someone that Quinn could have become if she'd been sitting in that detention class and met the MC instead.