Product : Microsoft, S2D [SDS]/2019, Datacenter
Feature : Flash Layer, Flash, Storage Support
Content Owner:  Herman Rutten
SSD, NVMe, (Persistent memory)
Storage Spaces Direct (S2D) supports both NVMe devices and SSD drives (SATA and SAS).

Supported flash media: NAND, 3D-NAND/V-NAND, 3D X-Point etc.

Supported Persistent Memory: NVDIMM-N.
NVDIMM-N is a DRAM/Flash hybrid memory module using flash to save the DRAM contents upon power failure.

The Windows Server Catalog does not list any NVDIMMs - including Intel Optane - that are either certified or compatible with Windows Server 2019. Also Azure Stack HCI Catalog does list Persistent Memory as a separate feature, but none of the hardware configurations so far leverage such hardware.