Hi Kasper,
You're remembering correctly that VMware products support PCI passthrough, but the important distinction is VMware Workstation vs. VMware ESXi.
VMware Workstation does not provide general PCI/PCIe device passthrough to a guest VM. This has also been confirmed in previous VMware/Broadcom Community discussions. Workstation can redirect certain device classes such as USB devices, but that isn't equivalent to PCIe DirectPath I/O.
PCI passthrough/DirectPath I/O is an ESXi capability. With ESXi, supported PCI devices can be enabled for passthrough on the host and then assigned directly to a VM. Broadcom documents that workflow under VMDirectPath I/O.
So, unfortunately, if your NPU is exposed by the host as an integrated or PCIe device, there isn't currently a supported way in VMware Workstation to simply add that physical NPU to the guest.
There could be an exception if the particular accelerator exposes functionality through a device/interface that Workstation already supports for redirection, such as USB, but that's device-specific and wouldn't be PCI passthrough.
If direct access to the NPU from the guest is a requirement, you would need a hypervisor/platform that supports passthrough of that specific device and also verify that the NPU, platform/IOMMU configuration, and guest driver support direct assignment.
Also, don't confuse Workstation's "Virtualize Intel VT-x/EPT or AMD-V/RVI" option with PCI passthrough. That exposes CPU virtualization extensions for nested virtualization; it doesn't expose arbitrary PCIe devices such as an NPU.
Hope this clears it up.