In order to effectively solve the problems of regional multi-line pure electric bus vehicle cooperative entry, passenger cooperative transfer and charging scheduling, a regional multi-line schedule coordination and vehicle scheduling optimization method considering the cross-line strategy was proposed to improve the system operation efficiency and service reliability. Considering the operation characteristics of pure electric buses, a dual-objective mixed-integer linear programming model with the constraints of departure interval constraints, operation energy constraints, and limited charging pile constraints was established to maximize the number of vehicle coordination times and minimize the total operation cost of the bus enterprise, and a differential evolution algorithm combined with a dictionary sequence was designed to solve the optimization model in order to determine the optimal vehicle dispatch plan for the routes. Compared with the initial schedule and vehicle scheduling plan, the total number of line synergies increased by 6.09% and the total operating cost decreased by 12.4%. The system optimization effect is obvious, which shows that the model can effectively improve the passenger transfer efficiency, reduce the risk of station crosstown, and reduce the operating cost of the enterprise. The proposed method for optimizing electric bus scheduling that takes cross-line strategies into account can effectively coordinate the scheduling of vehicles across multiple routes with the allocation of charging resources, thereby improving the operational efficiency of the bus system and the quality of passenger transfer services.