  The generation of spatially homogeneous spin polarization by application of
electric current is a fundamental manifestation of symmetry-breaking
spin--orbit coupling (SOC) in solid-state systems, which underpins a wide range
of spintronic applications. Here, we show theoretically that twisted van der
Waals heterostructures with proximity-induced SOC are candidates par excellence
to realize exotic spin-charge transport phenomena due to their highly tunable
momentum-space spin textures. Specifically, we predict that graphene/group-VI
dichalcogenide bilayers support room temperature spin--current responses that
can be manipulated via twist-angle control. For critical twist angles, the
non-equilibrium spin density is pinned parallel to the applied current. This
effect is robust against twist-angle disorder, with graphene/$\text{WSe}_{2}$
possessing a critical angle (purely collinear response) of $\theta_{c} \simeq
14^{\circ}$. A simple electrical detection scheme to isolate the collinear
Edelstein effect is proposed.
