Supercrystalline nanocomposites (SCNCs) are a new category of hybrid materials that typically consist of inorganic nanoparticles, functionalized with ligands on the surface and assembled into periodic structures. They have attracted growing attention due to their hierarchical architecture and intriguing functional properties (plasmonic, optoelectronic, biomedical). Understanding and tuning their mechanical properties is thus a crucial step to enable a broad set of applications. So far the mechanical behaviour of SCNCs has been partially assessed in terms of time-independent phenomena. However, time-dependent deformation is expected to play an important role, given the presence of organic constituents. Here, the time-dependent deformation behavior of SCNCs is investigated via nanoindentation, together with the influence of oscillations in continuous stiffness measurement (CSM) mode on creep deformation. It emerges that creep and recovery occur in SCNCs, both with and without crosslinking of the organic ligands (which changes the interactions holding the building blocks together from van der Waals to covalent), even though creep is less pronounced when crosslinking is present. Creep deformation does not completely recover even several weeks after nanoindentation, implying the presence of both viscoelasticity and viscoplasticity. The creep mechanisms were analyzed via derivation of stress exponent and activation volume. The large value of the stress exponent points at the occurrence of power-law breakdown, resulting from the localized high stresses induced by the Berkovich tip. The extremely small activation volume (~10^-5b³, b: modulus of Burgers vector), in turn, is attributed to the rearrangement of organic ligands in the sub-nm inter-particle gaps. In crosslinked materials, the stress exponent rises and the activation volume becomes smaller, reflecting how crosslinking impedes the movement of nanoparticles. Finally, the smaller creep displacement and higher stress exponent recorded under CSM mode suggest that oscillations can lead to the hardening of SCNCs, accounted for by strain rate sensitivity.