The Giants could build a package around Kyle Harrison
Normally, trading a borderline top 10 prospect in all of baseball like Kyle Harrison for a guy that could be a free agent at the end of season is not a good idea. However, there is nothing normal about Shohei Ohtani and to get the Angels' attention, the Giants need to be willing to part with big time talent.
Harrison has almost everything you want from a pitching prospect. He has three pitches that at least flash plus, is already at Triple-A knocking at the door of the big leagues, and he does so with his left arm which never hurts. His command can be a bit spotty at times, but the upside is undeniable.
This would be a tough pill for the Giants to swallow, but Ohtani may be worth it. San Francisco is in need of another starting pitcher and Harrison appeared to be a mortal lock to get called up soon. However, a hamstring injury right before the All-Star break is delaying his big league debut. Ohtani would immediately give the rotation arm the Giants need plus the added bonus of also getting one of the better power bats in the entire league.
What is crazy is that Harrison probably wouldn't be enough to get a deal done, but a package centered around him is a good place to start. The nice thing about Ohtani is that he fills two needs which makes the initial investment required feel better if you think about trading for him as trading for two elite players.