We examine the shadow properties of the rotating Fang-Wang black hole (RFWBH)-a regular black hole solution constructed via the Newman-Janis algorithm from a spherically symmetric solution in general relativity with nonlinear electrodynamics–described by the parameters mass, spin, and a deviation parameter M, a, and l respectively. In turn, we analyse the horizon structure and the ergoregion, demonstrating how l modifies these features compared to the Kerr solution. The shadow of a black hole is studied using celestial coordinates, revealing that increasing l reduces the shadow size and distorts its shape. By employing shadow observables - oblateness D and area A—we estimate the parameters a and l. We further constrain the RFWBH parameter space using recent Event Horizon Telescope (EHT) observations of Sgr A* and M87*, particularly through measurements of the angular shadow diameter. For M87*, at inclination , (a/M, l/M) ≤ [0.59, 0.07953], with l/M upper bounded for 0.59 ≤ a ≤ 0.8428 lowering with spin; at , (a/M, l/M) ≤ [0.39, 0.09869] with similar upper bounds on l/M for 0.39 ≤ a ≤ 0.8164. In the case of Sgr A*, the parameter space is constrained as follows: at inclination , the allowed range for a/M and l/M are [0,0.6692] and [0,0.0305], respectively; and for 90∘, the allowed ranges for a/M and l/M are [0,0.759] and [0,0.03075], respectively. We also analyse the energy emission rate, finding that the deviation parameter l subdues high-energy emission. Our results indicate that RFWBHs are consistent with current EHT observations and represent viable alternatives to astrophysical black hole models.
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