Answering (and solved) by myself (many thanks also to Amin Masoudifard):
https://communities.vmware.com/message/2886984#2886984
You understood MMU hardware assisted will avoid the use of guest shadow tables, and roughly, the result is to reduce latency to access to page tables.
But what about the CPU? Why can we activate CPU hardware virtualization here ("CPU/MMU virtualization: Hardware CPU, software MMU") and also on the other parameters ("Hardware virtualization: Expose hardware assisted virutalization to the guest os")?
What are the differences between the two CPU features? Because when you red documentation for "*CPU/MMU virtualization: Hardware CPU, software MM***U" and "***Hardware virtualization: Expose hardware assisted virutalization to the guest os*" they are talking together about using VT-X.
Here is the answers:
Do your VM are 64 bits are need to make nested virtualization? Check Expose hardware assisted virutalization to the guest os
=> this is for Guest optimization
Do you have VT-X/AMD-V instructions? To optimize VMWare VMM mechanisms, select CPU Hardware.
=> this is for Host optimization
Do you have Intel EPT/AMD NPT instructions? To optimize VMWare VMM mechanisms, select MMU Hardware.
=> this is for Host optimization