How about this:
Celtics receive: Giannis
Warriors receive: White
Bucks receive: Kuminga, Simons, Hield (contract filler), 4 1sts from the Celtics, 2 1sts from the Warriors
Why for Celtics? Celtics start Pritchard-Brown-Tatum-Giannis-Queta with Hauser, Hugo, Minott, Walsh off the bench. Still need more depth, but that's a contender.
Why for the Warriors? They flip Kuminga and Hield into White, who they were rumored to want. He's a better fit and allows them to make 1-2 more championship runs.
Why for the Bucks: Getting 6 legit 1sts plus two young players like Simons and Kuminga sets them up for a rebuild.
If Kuzma has to be in any trade with Giannis, then it gets more complicated, but not impossible. He actually fits right into our trade exemption, but then we'd need to flip his salary for someone making less than 13m a year to get back under the 2nd apron again. We have Hauser also as an asset to make that trade happen. The Jazz and Nets both have room in their cap to facilitate something.