One of the biggest problems with defending Giannis, is that one guy, no matter how great an individual defender, can't stand in front to draw a charge, because his Euro step is so big that he get just step around the guy. Double team will be needed, or serious help defense.
I would review all the film from the Toronto series. They had a good formula. Only problem is that, as we all know, refs swallow their whistles during the playoffs. So that same defense played by Toronto may not be effective in the regular season.