What changed?
Rogues could not use one-handed axes in original Vanilla WoW.
Forever status: This is tracked as a new class ability or a later-era ability brought into the reimagined level-60 game.
NEWDEMO CONFIRMED
One-Handed Axes
Rogues gain one-handed axe proficiency in WoW Forever.
One-Handed Axes
Weapon proficiency
Rogues can use one-handed axes in Forever; the Hack and Slash talent explicitly groups Axes and Swords together.