With the intensive development trend of offshore wind farms (OWF) in deep waters, flexible direct current transmission technology has become the best choice to integrate OWF clusters into the power grid, effectively improving transmission efficiency. However, although the development of clustering has reduced the investment in transmission submarine cables, the close distance between adjacent wind farms(WF) has also greatly reduced the wake effect of upstream WFs, which greatly reduces the power generation of downstream WF. This paper proposes a Stackelberg game model with offshore wind farm investors (OWFI) as leaders and offshore transmission operators (OTSO) as followers, aiming to reconcile the interests of various stakeholders while maximizing the benefits of the coalition structure. The developed game theory model effectively optimizes the transmission system planning of OWF clusters, improves the overall economic efficiency of the cluster, and promotes the sustainable development of clean energy. The case study shows that this method aligns with the interests outlined in the paper title, making it a promising solution for offshore wind power integration.