What is the difference between PCIe Gen 3 X2 and X4 SSDs? Can these two SSDs be used for laptops that support the PCIe interface? - Quora
Amazon.com: PCIe Gen3 x2 USB 3.2 / 3.1 Card ASM3142- PCI Express to 4-Port Type C HUB Internal Expansion Card Controller Adapter PCI Express Card Desktop PC Support Multiple INs : Electronics
QM2-4P-342 Quad M.2 PCIe SSD expansion card supports up to four M.2
PCIe x2 VS PCIe x4 SSD! Read/Write Speed two budget NVME SSD - YouTube
I harvested a PCIe Gen3 x2 NVMe 1.3 SSD from my older laptop, the problem is that its length is short. I've held it in place with some tape, it should hold.
Amazon.com: KingSpec 1TB M.2 NVMe SSD, 2242 PCIe Gen3x2 Internal Solid State Drive for Laptop/Notebook (2242, 1TB) : Electronics