Bulk sensor offset modification - template method

Still relatively new, but not a NooB.
I have 200 devices in Smartthings and am also running HA (Pi) for integration benefits. I have 10 motion sensors (old Iris ones) as well as some Wink and Ecolink that provide motion/temp/lum/humidity. The humidity readings seem to be off. But the 10 sensors seem to be off consistently in measure. They also don’t seem to actually send updated data if I apply +/-% offsets in the device configurations profiles.

Is there a way to make all of a particular device type and their humidity readings all overwrite with a consistent % or +/- offset in HA? In other words, if device model = 1234, make sensor.humidity = sensor.humidity * 0.7.

I realize I can do a custom sensor for each device, but that seems silly and brute-ish.