I didn't know which version to post so why not both?
H E A D C A N O N • Changelings, when they shape-shift into different creatures, are able to do what the creature can (eg: Magic, fly, strength, etc). For old changelings, the more love they absorbed, the more powerful that magic is. That is one of the reasons why love is important to them, other than not starving to death. For new changelings, using the creature they turn into's magic depends entirely on their energy and stamina, and not love like their old version.
• There are still a few unchanged changeling that follows the old ways, staying hidden for now until the moment is right to strike.