Correct me if I’m wrong but:
Zoyalai: Zoya driver, Nikolai passenger prince(ss). Nikolai will make pointed jokes about taking shotgun until they are less jokes and more pleas. As if she trusts him with efficiency in the first place…
Kanej: Inej drives, Kaz passenger princess. She’s objectively the smoother and calmer driver. He’s fine, but she would rather have control…and make life easier on his right leg.
Wesper: Jesper wants to drive, but Wylan will force him to be passenger princess for unfamiliar/long trips because when Jesper drives, he thinks he doesn’t have to obey signage if there’s no one else on the roads.
Helnik: Nina likes being the driver. Matthias does not like the speed at which Nina drives or amount she suddenly remembers a “shortcut” and merges or turns sharply enough to make him feel sick. He will play up the idea of “passenger princess” until she agrees and he can breathe again.
Genyavid: They actually trade off. There’s no drama. They’re both good, calm drivers. They switch who’s driving for every hour of time on the road and it carries over to the next trip.
Malina: Mal drives, Alina passenger princess. Mal is a tracker and she’s on the gps, so. I mean, canon has laid it out already. They’re also the most traditional-gender-roles couple by far, honestly.