While I don't love this trade for either team, I think it's semi-realistic.

The Pelicans will need a center when Jonas leaves in the offseason. I think Trey Murphy slides into Ingram's spot in the rotation, and Mitchell replaces/upgrades CJ's spot. Niang is really about matching cap, if the Cavs don't want to give him up, they may work in a 3rd team or something.

The Cavs need more size/shooting on the wings, which Ingram provides. Allen is kind of redundant with Mobley, and they struggle to have them both on the floor together in the playoffs due to spacing. McCollum is a downgrade from Mitchell, but the combination of him and Ingram overall is an upgrade. They may actually start Daniels alongside Garland to improve their size in the backcourt and bring CJ off the bench.

It's not perfect for either side, but I can imagine both teams feeling it's time for a shakeup, and I certainly would prefer this to Trae Young for the Pelicans, and assuming Mitchell indicates he won't resign in Cleveland, I don't know if Cleveland will have many better offers than 3 quality players, including a fringe all-star in Ingram for Mitchell.