Maybe have meet Purifier or another Siren.

Royal Navy rule the waves

Thing is, the sirens are extra dimensional, as in their main base is outside of the universe so it is impossible to reach. To defeat them the ships and their commander have to go full gurren lagann and break the unbreakable and shatter the heavens.
Also also, the universe of the game is a pocket universe built by the sirens which is why they can use things like time travel.

Glad to see ya back~ sorry to hear that you and your family went through all that. Hope you and your family are staying safe. As for Azur Lane, I know absolutely nothing about aside from fanart that a artist I follow does.

I believe that Naruto should join the Sakura Empire.

Eagle Union :D

Thematically speaking the Sakura Empire just makes the most sense no? Would also be a springbord to interactions with the Ironblood.

(Spoilers for anyone who hasn't delved deeply into azur lane lore)

Technically the timeline of the actual azur lane game is not the same as the timeline of WW2, more so a repeating of history due to the interference of the sirens so as to strengthen humanity. As you asked for reviews to not be 1000 pages long I'll stop there but I'm interested to see where you take this.

Well, all the other factions have their own bloodied, dishonorable actions. Germany had the Nazi party along with it's death camps.
The Russians had their Communism that honestly killed three times more of their own people then the Nazis killed in the Holocaust.
Japan had their Nanking, Bataan Death March, and Unit-731, America had internment camps for their own Japanese-American citizens and the two atom bombs, Britain and France had their ludicrously unjust Versailles Treaty that made Germany's societal situation bad enough that many thought the Nazis were a good idea, and the Italians for being fascist Italians at the time who only switched sides because they were losing. Each did good and bad things to their own country and each other. It might be interesting to see what you plan for this.

I vote eagle union since i feel like that is where he would most likely feel at ease since they have similar traits to him

Admiral! Its great to hear from you again! and with an Azur Lane fic no Less!? I swear its Christmas! I'll get to voting right away! I hope you are staying healthy and safe in these scary times. This looks amazing!

It's good to see you're still alive!