Z370 is just Z270 renamed (and it's almost the same as Z170), so a MB with this chipset should work with Windows 7 (but you must integrate some drivers, especially USB3, to be able to install it).
see this thread:
https://forums.mydigitallife.net/threads/drivers-to-install-win-7-on-a-win-10-native-computer.78573/
And this one:
https://forums.mydigitallife.net/threads/win-7-z390-chipset-an-old-guys-fears.78549/#post-1490012
You should also take a look at Windows 10 Enterprise LTSC, it come without Cortana, the store, Edge, and have a lot less of the telemetry crap.