She isnt the canon Azur lane Blücher. Instead she is the WW1 semi-armoured cruiser Blücher, built as a response to HMS Invincible but because of bad intel she was built to counter a ship that did not exist, meaning she was obsolete upon completition.

So, take a sip of mineral water with her and have some chit chat, she loves having those.

(She is mess, I can feel it.)