Why this could happen:

With the loss of Myles Turner, the Pacers desperately need more centers. I like Jay Huff, but the Pacers now have 3 middling bench centers and no bona fide starter to round out the lineup. Pacers give up their most expensive center and Jarace Walker for Onyeka and an SRP. I love Jarace Walker as a prospect, but he just has not gotten the opportunity in Indiana. As the 3rd string PF, he has only gotten spot minutes so far, but IMO has performed well. In this trade, He is bumped up to the second string after Jalen Johnson and finally gets a chance to get reliable minutes. The Pacers get a center with starter upside and a developing 3-ball. Onkeya really showed out at the end of last season, so I cannot imagine he is too happy with the front office bringing in Kristaps when he finally earned the starting spot. This trade gives him the chance to flourish in another city while providing a clearer hierarchy for the Hawks' center rotation. Isaiah Jackson is a great rebound hound who will back up Kristaps very nicely IMO.

Final Thoughts:

I think both teams would rather see their rosters without this trade, at least to start the year. I am intrigued by Jay Huff starting, and I'm sure with Kristaps' injury history, the Hawks would like some insurance in case he is out for an extended period of time.

Note: Totally forgot about Asa Newell, but I think Jarace, Asa, and Jackson could all come off the bench together with Kennard and NAW for a super fun bench unit.