Nah, Despair isn't really malicious like that. In fact, she's often a rather sympathetic character. Besides, I think DC has some kind of unspoken agreement that no one touches the Endless mythos but Gaiman, and though I know Geoff Johns has worked bits and pieces of The Sandman into JSA (Dream has sent a few messages to Doctor Fate from off-stage, and Brute and Glob trapped Sand in their demiplane the same way they'd trapped Hector/Fate in The Doll's House), he wouldn't use one of Gaiman's characters that way.