SmartThings is kind of in an interesting state right now as they are between multiple “old” integrations & “new” ones. Because of this things are changing frequently. They have a device handler that mostly works with the new app named “Inovelli 2-Channel Smart Plug MCD”. It is already integrated into their system. I don’t think the endpoints work with Alexa or Google Home though. Also, last time I checked, it didn’t allow you to use the endpoints in their “Automations” setup. Maybe that has changed but I haven’t checked recently. This was supposed to be the way they were going forward with multi-channel devices and it is a device handler that they worked on.
I think the best option that is working today is a modification that I just made to the device handler in our github. You have to delete the child devices that are currently there and recreate them by saving the preferences (after you update the handler) for the device or re-include the device, but the new child devices should work as expected (at least as of right now).