For anything to run locally on the v2 hub it needs to be pushed via a firmware update from SmartThings, for the device handler to have a chance at running locally it would need to be officially published by ST.
We don’t have the ability to switch DTH’s on the mobile app.
If you included the device fingerprint in the DTH and published it before adding the device it may auto select that dth, but you should check in the IDE.
For a device that was already added to the network, or if you didn’t add the fingerprint you will need to change th device to the newly created/published device handler(will run on cloud not locally) in the IDE:
In the IDE click device tab
Click on a device
Under Device handler find the newly created dth, It should be at the bottomish of the drop down
Device will pretty much instantly switch over. Depending on the device, sometimes it takes some of the data a minute or a refresh/configure or two to populate.