I am not able to reproduce your errors. The most recent releases of device driver code for the Mi Cube and Xiaomi Honeywell Smoke Sensor can be saved without error as Hubitat hub device drivers on my Hubitat Hub which is running the most recent hub firmware as of today.
My guess is the same as @bertabcd1234:
The SmartThings hub does not have the
PushableButton capability, which is why I guess that you may be trying to save Hubitat device drivers as Device Handlers on a SmartThings hub.