The NY trade is the only one that I think all 3 teams might do. And if Miami would do that I'd rather just have KO and Dragic than Barnes. I also don't think the Kings want anything to do with Morris, though I do think a 3 team trade is feasible between the Kings, Clips, and C's.
Boston - Barnes, Morris, Beverley, Zubac
Los Angeles - Walker, Thompson, Whiteside
Sacramento - L. Williams, Kabengele, Langford/Nesmith, J. Green
I think that trade makes way more sense for all 3 teams.
Boston would then have a starting 5 of Beverley, Brown, Tatum, Barnes, Theis with a playoff rotation of Smart, Morris, Zubac, R. Williams, Semi and a deep rotation of Pritchard, Teague, G. Williams, Langford/Nesmith with Fall, Waters, and Edwards in suits. That is a much better team than the current one because it adds a lot of depth and it adds a potential long term center in Zubac and a nice solid 3rd/4th option in Barnes (who is still young enough to be able to contribute in a couple of seasons when Tatum and Brown are in their primes).