As VMware Workstation is a desktop application, it still has to play by the rules of the host OS.
As VMware Workstation is available on both Windows and Linux, the CPU scheduling would follow that of the corresponding host OS. Similarly on the Fusion on macOS would have to follow the CPU scheduling rules of macOS.
For example, with Workstation on Windows, every running VM is associated with a process called vmware-vmx.exe with normal priority (8). There are multiple processes that are needed by a running VM (e.g. VMnat.exe if the VM is using NAT networking, VMUSBarbservice for access to USB devices, etc).