Hi:
Below is the link to the service manual for your notebook.
http://h10032.www1.hp.com/ctg/Manual/c06325755
Chapter 1, pages 4 & 5 have the supported M.2 drives.
The manual indicates the M.2 slot only supports SATA drives, but it also indicates it supports Intel Optane memory, which is NVMe.
So, I would conclude the slot also would support a NVMe drive like the Samsung 970.