So, any clues are we going to see Checkmate in the new DC comics?

We've had it mentioned in at least one comic so far. The one that comes to mind was in O.M.A.C. Checkmate will be pretty involved in that title, by my understanding. I don't remember a mention thusfar in JLI, but it seems likely that there will be a tie or two there, perhaps eventually also in Suicide Squad.

i think they are O.M.A.C's foe

I hope they'll get their own series again asap. Checkmate was mentioned by Amanda Waller in the second Suicide Squad comic and I hope they'll bring back characters like Tommy Jagger and Josephine Tautin.