The Bucks are not trading Giannis - I have no idea why anybody would even ask this . I think you would have a better chance of getting Durant from Golden State.
Even if they would trade him, I'm still not sure I'd give up that much for one guy. We have already seen how good the Bucks are with Giannis surrounded by decent but not great talent - they are barely a playoff team.
Bring him here without Kyrie, without Tatum, and with the uncertain future of Hayward...and things aren't looking much better.