My last sentence was bad written, my actual config ssd and m.2 adapter should not work according to manual like 2 m.2 adapters, but is working flawless. I understand if I would replace ssd by another pcie adapter it would work.

If you have and ssd m.2 you can test if same config than me is working on your machine.

I also have an asus prime 270a, z170 and z270 are similar and is working with two m.2 adapters.