How Kongō moved along the battlecruiser spectrum

Where did the Kongō class sit in the transition from battlecruiser to fast battleship?

It began toward the battlecruiser end and moved into the fast-battleship overlap after reconstruction.

Ship classification can change over a long service life. Kongō began as a battlecruiser, with the speed and compromises implied by that role. Later upgrades moved the class toward the overlap between a fast battleship and a reconstructed battlecruiser. The label should follow the ship's actual configuration and role rather than remain frozen at launch.