Likely a stylized form of Nico, a short name from Nicholas meaning victory of the people.
Nieco is likely a stylized form of Nico, a short name from Nicholas meaning victory of the people. By lengthening or reshaping that root slightly, the name gains a more individualized and modern appearance.
Nieco feels concise, friendly, and lightly international. It has the accessibility of a nickname-name, but its uncommon form makes it feel deliberate rather than merely casual. That combination of familiarity and novelty is often what gives short modern names their staying power.