The OP already has the bulbs connected directly to the SmartThings hub. The question was about removing it from the ST Hub and moving to a Hue bridge.
You will find many threads discussing this issue, because the smart things hub does not support the ZLL profile. It only supports the ZHA profile.
When A Hue bulb is attached to the Hue bridge, it uses the ZLL profile. If instead you connect it directly to a smartthings hub, it will change to the ZHA profile.
For most brands of bulbs, that is not a problem because the individual bulb can be factory reset using a “blink method” where you turn the individual bulb on and off power rapidly in a specific pattern, and then it resets itself.
Phillips chose not to do that for their bulbs, perhaps because they were concerned about children playing with a light switch accidentally resetting the bulb. (It can happen.) Their intent was that their bulbs only be used with the Zll profile, and it is possible for a bulb associated with one ZLL network to be transferred to a different ZLL network using the “touch link” or “bulb stealer” method.
However, the ZLL methods do not work with a bulb using the ZHA profile, because in that profile there is a network coordinator, and that coordinator’s information is stored in the device at the time of pairing. It has to be reset before the bulb can be moved to a different Coordinator. Beyond that, if you want to move to A ZLL network, the bulb has to be reset to use the ZLL profile.
All of this is why the official SmartThings position is that you should only use hue bulbs that are attached to a hue bridge. The smart things hub cannot reset anything to A ZLL profile. It doesn’t use that profile. And unlike Crees,
Osrams, and GEs, Hue brand bulbs cannot be individually reset with a blink method.
Hence the need for an additional device that can force the bulb to reset to the ZLL profile.