To address the challenge of aligning the diverse interests of multiple stakeholders on both the supply and demand sides in grid voltage sag mitigation strategies for distribution networks, this paper proposes a customized allocation method for dynamic voltage restorers (DVR) and distribution static synchronous compensators (D-STATCOM) oriented toward multiple stakeholders. First, based on the heterogeneous distribution characteristics of voltage sag events, the unquantifiable and nonlinear relationship between mitigation effectiveness and investment cost is analyzed, demonstrating the necessity of a multi-objective optimized configuration scheme. Second, an allocation strategy is then proposed to reconcile inter-stakeholder differences in mitigation-investment preferences while ensuring intra-stakeholder demand consistency. A multi-objective optimization model is developed that incorporates both investment cost and mitigation performance. Given the high non-convexity of the proposed model, a multi-objective snake optimization algorithm enhanced by an elite opposition-based learning strategy is employed to obtain the Pareto optimal solution set, and a fuzzy decision-making method is used to select the final configuration scheme. Finally, case studies are performed on the IEEE 34-bus system, and the results confirm that the proposed method effectively integrates the diverse interests of various stakeholders, enabling a coordinated and customized optimal configuration of voltage sag mitigation devices.