Adding Nitehawk AX8 model EAX80 ax6000 mesh extender to Orbi Pro

I have an Orbi Pro and I want to know whther adding a AX6000 msh extender by Netgear will have any effect on the system. If I understand correctly the system will set up another ntwork for the ax6000 and then will downgrade to the slowest backhaul of any additional mesh extender. So my questions is twofold. First, is the backhaul of the AX6000 slower than the orbi?   Secondly, can I set upo the 6000 as a mesh extender since I happoen to hav it anyway and can it be set up without haviung it's own network name? Would the orbi app tak care of thgis?

Thanks

Ray