Joseph1957: Zoë was not a shifter at the beginning of Dreamfall. When Zoë travels from Stark to Arcadia, her body remains behind in Stark, only her consciousness travels, however, this is not the case when coming back from Arcadia, her whole body returns. Remember when Na’ana hypnotised Zoë to send her back to Stark and her body vanished out of her clothes? However, later, in one of the episodes of Dreamfall Chapters, Zoë puts on a dream machine (un-licence version) when she is with Mira and others, in the workshop. But this time things have changed - Zoë’s whole body is now able to completely vanish from Stark (even the clothes she is wearing as well).
Does this mean she “is” now a shifter? Maybe, Zoë does have a hidden talent in shifting between worlds (just like April) and the dream machine is not really needed, she is just not aware of this yet.
Zoë was never a Shifter, and will never be. She's a Dreamer. What exactly that means is not entirely clear, but there are likely theories.
The central one of them is, of course, that Zoë was never really in Propast to begin with. Back in Dreamfall, Zoë was dreaming herself into Arcadia while her body remained in Venice. In Chapters, it seems Zoë is dreaming herself into Stark/Europolis from her coma hospital bed in Casablanca. That was a strong theory by the end of Book 2 (ending cutscene glimpse!!), so there was a good bit of discussion as to what would happen if she put on a Dreamachine. I personally thought it couldn't work, but I was wrong.
The Dreamachine is still a pathway for Zoë's dream entity to reach Arcadia, only this time her dream entity was travelling already by the time she puts on the device. It vanishes from Stark as it travels to Arcadia. The body always remains in Stark/Casablanca.
Zoë never 'really' reaches Arcadia and never 'really' reached Europolis in Stark, as a Shifter like April would.
Exactly in line with this theory is of course the issue with the clothes. Dreamer Zoë's consciousness always arrives in Arcadia clothed appropriately. The dream self can be molded to that degree, obviously. Shifter April Ryan however... she arrives in modern attire and most of the time in her underwear. :)