The definition of a pseudovector is that it changes sign when you change the orientation of the ambient space. You start with the vector field $\mathbf v$ and it corresponds — given the duality coming from the metric — to the $1$-form $\omega_1$. Where does $\omega_2$ come from? Well, $\omega_2 = \star\omega_1$, and the Hodge star operator changes sign here when you change the orientation on $\Bbb R^3$. Thus, the recipe for $\mathbf B$ depends on the orientation choice.