We first heard about The Imperial Handbook earlier this year and it was finally officially announced without a word about whether it fits into Legends or the new canon. Well, Mark Hurliman of Star Wars Report got an answer: It’s Legends.
This isn’t a big surprise – predecessors The Jedi Path, Book of Sith, and The Bounty Hunter Code are clearly Legends as well – but with Lucasfilm choosing to leave things vague (for sale purposes?) it’s good to have this nailed down.