Dear @Wenchao.Shen,
The 6x6 mass matrix for the full system (rotor + drivetrain + nacelle + tower + floater + ballast) of the NREL 5-MW baseline wind turbine atop the OC4-DeepCwind semisubmersible is available in my post dated Feb 13, 2020 in the following forum topic: OC4-DeepCwind semisubmersible - WAMIT Files.
Best regards,