I think it would be reasonably straightforward actually. They'd include Wiggins, Kuminga and a salary filler, plus they own all their picks except 2030 which goes to Washington but is 1-20 protected, so they could easily claim it back by offering them a couple of second round picks instead. If I'm Phoenix, I'm taking that deal as long as I get their first round picks unprotected or with very light protections... but they seem to want Butler.
More noises that Phoenix are listening to offers, I could also see Rockets being interested. They own many of Phoenix future picks so could just give them back in return, this makes total sense for Phoenix if their intention is to rebuild... which again, I'm not sure it is given that they want Butler (I don't get it, swap Durant for Butler and you have a much worse, and equally expensive team with no upside).