Who do you ship with Isa?
the answer to this is largely the same as what I answered for Carla: I don't really have any Isa ships that I actively seek out, but would be willing to engage with basically any ship between her and someone within her approximate age range. So, like, the rest of Team Isa, the Enchancia kids, Cat, Ari, uhhhh, Lucas? Is that all the kids? There's probably someone I'm forgetting that I'll remember right after I post this.
I stepped back from this post for a second to make tea and think about if I was forgetting any kids but instead I was thinking more about Isa/Cat bc like, Cat is (iirc) the only other one of the kid characters she hangs out with that is Just As Into Science and Engineering as she is, and they'd have like, ample opportunities to bond over different aspects of it.
Like I could see their feelings developing while they were working so closely together on the gondola designs, and Isa drawing sketches of Cool Bugs she finds, or experiments from her college class, and sending them along with letters to Cat to get her thoughts, and Cat commandeering a wing of her palace to set up a conservatory where they can raise all the Dananus plexippus they want and the two of them hang out in the butterfly room together when Isa visits and aaaaaaaaaa-
Ok I take back what I was saying in the first paragraph, my preferred Isa ship is now Isa/Cat. (although that said I'd still engage with other Isa ships without complaint, it's *very* rare for me to prefer a ship to such a degree that it removes others from the table)