Temperate sub-Neptune exoplanets could contain large inventories of water in various phases, such as water-worlds with water-rich atmospheres or even oceans. Orbiting close to M-dwarf stars, these planets receive large amounts of radiation, especially during flaring events, which may strip away their atmospheres. Both space-based and ground-based observations have shown that many exoplanets likely contain photochemically-generated hazes. Haze particles are important for the potential generation of organic matter and may impact the evolution or origin of life. In addition, haze layers could provide a mechanism for lower atmospheric insulation and ultimately atmospheric retention. M-dwarf stars are known to have higher stellar activity than other types of stars, and stellar flares have the potential to accelerate atmospheric escape. In this work, we present results on laboratory investigations of UV radiation effects simulating two different stellar flare energies on laboratory-produced exoplanet hazes made under conditions analogous to water world atmospheres. We find that both simulated flares altered the overall transmittance and reflectance of the hazes, and higher energy flares make those alterations more pronounced. On a larger scale, these hazes diminish over the simulated flaring period. Our results provide important insight into the effects that stellar flaring events have on potential exoplanet haze composition as well as the ability for water world-like exoplanets to retain their atmospheres.