According to tamron.eu, the SP 150-600mm F/5-6.3 Di VC USD G2 (model A022): From serial number 035591 or firmware 2.0 is compatible with Z6/Z7 and FTZ.

Hello Johhotz,
If you have an FTZ adapter for your Nikon Z6, then all F bayonets are compatible with the new Nikon Z bayonet, whether they come from Tamron, Sigma or Nikon.
Regards
Philippe

Dear Johhotz

I use the Tamron lens with a Nikon D500. It works very well. The autofocus and the stabilisation in the lens work quickly and reliably. I would buy the lens again in a heartbeat.

But your Nikon Z6 has a different coupling Nikon Z bayonet and not Nikon F like my camera. I don't know the Z bayonet. I don't know if there is a different version of the lens. I also can't judge whether it will work reliably with your camera.

I would ask Nikon or Tamron directly which version fits and whether it is fully compatible.

Many greetings Martin