As noted, Pro Wrestling Sheet reported yesterday that The Hardys have been offered new WWE contracts. PWInsider.com confirmed the report and they added that The Hardys returning to the WWE is "a matter of when, not if."
The report also notes that the deal is only for Matt and Jeff, as Reby and Senor Benjamin have not been offered deals. One major hurdle to an agreement has been schedule. The WWE typically wants its talents to work full-time schedules, with very few exceptions. The Hardys are not interested in doing that.
As for their gimmick, Matt & Jeff are currently in a legal battle with Impact Wrestling over the rights to the "Broken" gimmick, which is why they are not fully using it right now in Ring of Honor.