The Holo-Pearl is a reflection of Pearl’s rigid adherence to logic and form. Without Pearl there to command it, the hologram becomes a cold, repetitive machine that nearly hurts Steven.
See a before and after regeneration?
When Pearl finally returns, she debuts a new character design (losing her sheer floor-length skirt for a shorter tunic), which she keeps until the Season 1 finale. [S1E16] Steven the Sword Fighter