Let’s clarify a few issues here
You can’t use a PCIe/NVM M.2 SSD via the systems SATA port.
Apple’s blade connection is custom offering a few other signal lines as such a M.2 really don’t work that well.
OK, What is a better option? While a bit more expensive OWC offers a pin compatible SSD, you could also get a real Apple SSD.
IFixit offers the [product|IF174-063]
And here’s a source for the real Apple SSDs [https://beetstech.com/product/sspolaris-ssd-256gb-512gb-1tb-2tb|Apple custom SSPOLARIS SSDs]