Any guys know about this horrible phenomenon from Metahumans?

I just get all meshes and functions from Metahuman BluePrint in BP_FirstPersonCharacter. But I faced this error following video… I think there is some problem in Mesh0 Component. When I set Body mesh for leader pose instead of Mesh0 Component in construction func, It’s not appeared. I can’t stand vomiting anymore…

I use ‘Play as Listen Server’ in net mode and run new editor window when I test play. Player num is 2.

Can anyone guess the cause?