i would call it a poleaxe (pollaxe) too:
The weapon head is clearly inspired by pollaxe designs.
Although the ingame weapon length is not common for a pollaxe, its longer than usual pollaxe.
So the attacks using the bottom of the shaft won’t necessarily would be a prominent or effective move with such a weapon irl, imo.
Generally, the ingame weapon would be less thrust oriented, and more chop oriented, relative to usual historical halberd used for formation fighting. It would be a great weapon for dueling and out of formation fighting imo.