Jeff Hardy was planned for an NXT run of some sorts.
Not only was Jeff Hardy factored in a lot of plans on the WWE main roster until January, he was planned for an NXT run as well. Hardy was released by WWE in December, and it left the company scrambling, as Jeff Hardy was originally planned to be the "Shaman" for MSK. Just days before the reveal was to happen, Hardy was released by the company, and Matt Ridddle had to rush to film content with MSK to make it work.
We're told there were "numerous" segments on the cutting room floor that featured Jeff Hardy as The Shaman. Since then, Riddle has joined MSK in a match with Imperium, but we haven't heard if the original plan with Hardy called for that to happen as well.
Hardy was released days before the reveal after refusing rehab, which he and members of his immediate family have claimed that he didn't need.