The synergy of different offshore renewable energy resources is expected to significantly reduce the cost, save marine space, contribute to energy security, and accelerate energy independence by providing clean and affordable energy to the off-grid and isolated small Greek islands, which are still dependent on fossil fuels. In the frame of the Greek project NISOS, several studies considering the wave energy potential of two small Greek islands, have been already performed, while the development of offshore wind farms constitutes an important national strategy. In this respect, a preliminary assessment of two potential hybrid offshore projects at Antikythera and Halki islands is performed. For the wind and wave climate analysis, long-term (1993–2020) data are obtained from the reanalysis wind dataset CERRA at 150 m and 100 m height above the sea level, and the reanalysis wave product MEDSEA_HINDCAST_WAV_006_012, respectively. The combined offshore wind and wave energy production is estimated at the most energetic offshore locations, using two different offshore wind turbines and a downscaled model of a wave energy converter. From the numerical results, it is evident that the highest hybrid energy production is encountered around Antikythera Isl., which is the most favorable area for the development of hybrid offshore wind – wave energy projects.