In Chapter 72 of the SNK manga, three previously unseen Squad Leaders were introduced in a meeting with Erwin Smith, Hange Zoë, and Levi Ackerman. In the just-released Chapter 75, Erwin mentions three of the Squad Leaders' names: Dirk, Marlene, and Klaus. I've reviewed both chapters extensively, and have been able to somewhat determine which of the Squad Leaders.
The blond woman on the couch is most likely Marlene, the leader of Squad Marlene, as she is the only female in the room besides Hange (unless you consider Hange to be male in the manga, in which case she is the only female). The blond man sitting next to her can be seen giving orders to the squad protecting the horses, meaning he must be Klaus, the leader of Squad Klaus (who Erwin mentioned was guarding the horses). The blond man sitting in the chair next to Hange is likely Dirk, as he is seen accompanying Erwin for the entirety of Chapter 74, but disappears after Erwin orders Squad Dirk to leave (indicating that he left because he is the leader of Squad Dirk). No word on the name of the vaguely Kuklo-looking guy, though.
My conclusions on who is who may be wrong, so I wanted to get some feedback from the wiki before I created pages for these characters.