We investigate self-bound quark stars in a flavor-dependent quark-mass density-dependent model with an excluded-volume correction. We chart the parameter space at zero pressure to identify self-bound regimes, including parametrizations in which self-bound two-flavor matter undergoes a genuine first-order $ud\to uds$ transition at finite pressure. We construct cold, $\beta$-equilibrated stellar sequences and compute the corresponding global properties (mass-radius relation, tidal deformability, and moment of inertia). For a wide region of the model parameter space, we find that the onset of a $uds$ core occurs before the maximum-mass configuration is reached, yielding self-bound hybrid stars that follow the typical strange-quark-star sequence morphology but develop a characteristic kink at $p_c=p_{\mathrm{tr}}$ along the stellar curves. The excluded-volume parameter $\kappa$ controls the stiffness of the equation of state and thus masses, radii, tidal deformabilities, and moments of inertia; intermediate repulsion typically reconciles $M_{\max }\gtrsim 2M_{\odot }$ with current astrophysical constraints. We further identify two equation-of-state insensitive trends—dimensionless moment of inertia versus compactness and gravitational versus baryonic compactness. These results provide model-guided priors and tools for discriminating between hadronic and self-bound equations of state with multimessenger data.

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• Nuclear matter in neutron stars
• Quark matter