I probably should have done this before I started tagging the other day, so if this gets rejected I will undo my tag changes. I assumed the lack of sister and incest tags for sister ships in Azur Lane was just an oversight. I apologize in advance if this is the wrong way to address this.
I believe Azur Lane sister ships should be tagged as sisters, and in cases of yuri tagged with incest.
In game during events and in voice lines, in official works such as comics and the anime, and in the community, sister ships are referred to as sisters and have sisterly relationships. Some examples are the Cleveland class making many references to each other as sisters in their voice lines, as well as Pola and Zara, or Indianapolis and Portland, and others. Many more don’t specifically say “sister” but reference each other repeatedly and show they have a sisterly relationship, such as Prinz Eugen, Admiral Hipper, and Blücher.
There was a previous thread from 8 years ago referring to Kantai Collection. Kantai Collection is obviously different from Azur Lane so I don’t believe that applies here, especially as I don’t believe Kantai Collection treats sister ships as sisters like Azur Lane does.
The two main arguments in that thread, in case there is an argument that they apply to Azur Lane, were some of the ships not knowing each other previously (“the Fubukis meeting each other for the first time”), in Azur Lane, the ships operated outside of the port and already knew each other, and have past memories from before being Kansen, and even if they didn’t, not knowing a sibling previously doesn’t make you not related. The other is they are personifications and not biological, but in this context/universe they are personified as sisters, and Fate tags relationships like Artoria and Mordred as sisters/incest fate_(series) incest.
If the change to tagging for sister and incest is approved for Azur Lane, I will finish tagging the existing posts.