Adjust MMD rig to Blender rigify rig.
The rig is easy to animate and has facial rig too if you need it. It's easier to animate than shape key I suppose.
The 4 models are finished and share it for free. :)
And, There are 3 movements inside the file. You can directly apply to see how the rig can be used.
I get The MMD file from HERE:
Zhongli:
https://www.bilibili.com/blackboard/activity-JgjL9OCE1Z.html?spm_id_from=333.337.0.0
Eula, Hu Tao, Xingqiu:
https://www.bilibili.com/blackboard/activity-raop07Ymhm.html