Short review
Important issues are raised, and it is sometimes really sweet but ultimately reads like a moral education handbook. Repetitive, redundant, trite, and too on the nose.

Long review
Maybe this book is not for me. Or I didn't read it at the right time. What I found heartwarming in the first book more often than not annoyed me in the second. It reads almost like a moral education handbook: there is a lot of telling, as in characters constantly explaining things to others. Don’t get me wrong: important issues are being addressed, important questions raised, they’re just too on the nose. Speaking of too on the nose: “Janine Router/Rowter”? Really? It’s kind of ridiculous.

Somewhere Beyond the Sea almost taints the overwhelmingly positive impression I had of The House in the Cerulean Sea. Perhaps these books follow a formula that I liked once but did not need a second time around. That’s why I cannot say “if you loved the first book, you’re gonne love the second.”
 

Repetitive, redundant and trite are words that kept coming to mind while listening to this. It did not help that I didn’t like some of the voices the narrator of the audiobook used, especially Arthur’s. He sounded incredibly whiny the entire time, and I reckon I would have liked this book more if I had read a physical copy like I did with the first one.

Generally, I appreciate the positive queer representation. I appreciate the author’s wish to be an antithesis to JK Rowling. But he really shoves it into our faces.

One last point—or rather: rant—about trans/nonbinary representation: it exists, but the two nonbinary characters I’m thinking of are either only briefly mentioned or barely have any lines. With the found family setting, with an ensemble cast like this, it would have been SO EASY to actually include a trans and/or nonbinary kid who lives on Marsyas. Especially when there’s a new addition anyway! An unregistered one at that! This I don’t understand. It didn’t bother me in book one, because there wasn’t, as far as I remember, any mention of transphobia (or queerphobia in general for that matter) in this world. But in Somewhere Beyond the Sea, trans people are mentioned several times! Not only in the dedication and afterword (which I liked, don’t get me wrong), but also in the text. Arthur mentions the mistreatment of trans people during his testimony, and later the phrase “guys, gals, and nonbinary pals” pops up—in the narrative, mind, not in the dialogue—which I thought was incredibly cheesy. It would have been so much better to just include an important nonbinary character (why not David? Such a missed opportunity) instead of the empty and surface-level name-dropping. I realise I’m being nitpicky, because the author at least included me/us. However, if you dedicate your book “to trans people the world over” but fail to include an important trans character and make the meagre nonbinary representation feel like an afterthought, I think I’m rightfully nitpicking. I know, I know, the entire magical children/adults thing is an allegory for all kinds of marginalised people, including trans kids. I get that. But then why introduce queerphobia in the first place? Rant over.