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.