The ramp up/ramp down is most likely a parameter in the switch settings. If it is possible to change that, you would do it by reconfiguring the device if you have a device handler capable of changing those Settings.
So first you need to figure out what those parameters are, and then the device handler would have to be updated to allow the changes.
If you’re controlling smart bulbs, it might be a separate parameter in the bulb settings as well. So then you have to look at the device handler for the bulb.