At low temperature, methyl groups act as hindered quantum rotors exhibiting rotational quantum tunneling, which is highly sensitive to a local methyl group environment. Recently, we observed this effect using pulsed electron paramagnetic resonance (EPR) in two dimethylammonium-containing hybrid perovskites doped with paramagnetic Mnsup.2+ ions. Here, we investigate the feasibility of using an alternative fast-relaxing Cosup.2+ paramagnetic center to study the methyl group tunneling, and, as a model compound, we use dimethylammonium zinc formate (CHsub.3)sub.2NHsub.2Zn(HCOO)sub.3 hybrid perovskite. Our multifrequency (X-, Q- and W-band) EPR experiments reveal a high-spin state of the incorporated Cosup.2+ center, which exhibits fast spin-lattice relaxation and electron spin decoherence. Our pulsed EPR experiments reveal magnetic field independent electron spin echo envelope modulation (ESEEM) signals, which are assigned to the methyl group tunneling. We use density operator simulations to extract the tunnel frequency of 1.84 MHz from the experimental data, which is then used to calculate the rotational barrier of the methyl groups. We compare our results with the previously reported Mnsup.2+ case showing that our approach can detect very small changes in the local methyl group environment in hybrid perovskites and related materials.