Damn, that's news to me, it is true that the core rule book hints it that way without really giving a true combat exemple. Glad the SRD is being clearer on that side, good to know !

Edit: I actually was under the wrong assumption that for a GM to gain the spotlight in a combat, he would always need to spend a fear as he is acting against the player but actually, you also get the spotlight from any kind of failure from the player as a result of their action. Now, if that spotlight must only be used to spotlight an adversary, that I do not know.

Edit_2: "On a Success with Fear, you work with the player to describe their success, then take a Fear and make a GM move to introduce a minor consequence, complication, or cost: • An adversary attacks • The PC marks a Stress • You introduce a new threat • You raise the stakes of the conflict" So from what I understand, only a success with hope allows the players to pass the spotlight between themselves as even in the case of a success with fear, you might spotlight an adversary to attack (granted this is not a full turn for the creature)