If this is your model I can not find anything about NVMe M.2 support.
HP EliteOne 705 G1 23-inch Non-Touch All-in-One PC - System board - Gladiator - BIOS Simulator
http://h20464.www2.hp.com/results.htm?SID=6953322&MEID=11390FDF-06BC-413F-8612-03914F496716
HP EliteOne 705 G1 23-inch Non-Touch All-in-One PC - System Board - Gladiator - System Board Viewer
http://h20464.www2.hp.com/results.htm?SID=6953322&MEID=3C0F59A8-D0FE-41F6-B76C-BC1C7725187A
REO