Floating breakwater layouts require flexible adjustment to accommodate sheltered area bathymetry. However, most studies have focused solely on straight layouts and have neglected the influence of complex nearshore bathymetry and structures. This work investigates streamlined-layout double-row floating breakwaters with wing plates designed for a specific port. Wave attenuation performance, motion responses, mooring tensions, and surface wave pressures under realistic nearshore conditions are systematically evaluated through a water tank experiment. The results demonstrate that the wave attenuation performance improves as incident wave height and period decrease, with the attenuation rate increasing by 6.32~11.05%. However, both the motion responses and the uplift pressures on the head and tail modules change slightly. The maximum prototype-scale changes in the maximum amplitudes of surge, heave, and pitch are +0.0625 m, −0.488 m, and +3.8523°, respectively, and the uplift pressures on the head and tail modules exhibit maximum changes of +2.3 kPa and −5.6 kPa, respectively. Additionally, wave reflection induced by nearshore structures influences both harbor tranquility and breakwater motion response.