We examine generalized almost \(\eta \) -Ricci solitons on spacetimes, providing two explicit examples to confirm their existence. Under the assumption that the potential vector field satisfies conditions such as parallelism, conformality, Killing, concircularity, or torse-forming behavior, the manifold is shown to be a generalized quasi-Einstein spacetime. Furthermore, when the soliton field coincides with a unit timelike torse-forming vector, the gradient of its governing scalar function aligns with this vector, ensuring a perfect fluid structure. We also demonstrate that \(\mathcal {W}_2\) -flat spacetimes admitting such solitons inherently possess generalized Robertson–Walker geometry alongside perfect fluid properties. Finally, gradient solitons in this context correspond to a generalized quasi-Einstein spacetime.
