Abstract: Recently, several pentaquark states P-css, with global flavor (c) over bar ccssn, have been predicted within a theoretical framework based on unitary coupled channels. We study theoretically the feasibility to observe the P-css with I(J(P)) = 1/2(1/2(-)) in the decays Xi(c)(b) -> eta eta(c)Xi(0) and Omega(-)(b) -> K-eta(c)Xi(0). Indeed, within the model, the eta(c)Xi(0) channel is the lowest mass pseudoscalar-baryon channel to which this pentaquark state couples, thus we can expect to observe its signal in the eta(c)Xi(0) invariant mass distribution of the mentioned decays. We identify the dominant weak decay processes and then implement the hadronization into the different meson-baryon channels in the final state, linked by flavor symmetry. The dominant meson-baryon final state interaction is then implemented to generate the full amplitude, implicitly accounting for the dynamical emergence of the pentaquark states. We obtain a clear Breit-Wigner-like resonant signal in the spectrum of the Omega(-)(b) decay, exceeding that in the Xi(0)(b) decay by two to three orders of magnitude. In the case of the latter decay, the resonant state would manifest as a significant dip in the spectrum. We study the feasibility of searching for these b-hadron decay modes and analyzing their resonant components using the current and future data samples from the LHCb experiment.