Drop Mock Trial and Japanese School. I’m sure you love them but something has to give. Presumably you’ve been doing Japanese School for quite a while, so that you’re now just polishing skills. Same thing for Mock Trial. I’m sure you love both of them but you have to prioritize and these two are the most “non necessary” (in the way skating is “necessary”).
Also, don’t take the SATII. Unless you need external validation in your native language (ie., you want the colleges to know that you know English, Z Language, and a Foreign Language learned at school) these will not bring any advantage. Ok, you’ll lose the money, but it’s not that much. If you feel really bad you can probably earn it back in one day at a part-time job you could have over the Winter break :). That would free up more time for what matters AND will yield money (TOEFL and PSAT).
You don’t need to prepare for the TOEFL. Check out what the rubrics are for the writing, familiarize yourself with the format = total 1 hour, once. That’s it.
Also, aim for a high score on the PSAT - aiming for a 1550 SAT in the Fall of Junior Year is too much stress, even if aiming for 1500+ for Spring junior year may be a goal. So, prepare for the PSAT, including by taking the SAT without that crazy score pressure, but mostly work on the PSAT. There are several big scholarships that come from being top 1% on the PSAT so it’ll be time well-spent. Also, it’s easier than the SAT so you don’t need the same amount of time to prep. Be aware it’s in October though, so you don’t have much time to be ready. You can prep for the SAT in the Winter and take it in March.
Top 20 universities don’t really have merit scholarships. Since you’ll need merit to attend college, run the NPC and cross out any university that doesn’t match your parents’ budget. If you don’t know what that is, now’s the time to ask.
Doing all this should allow you to cut about 15 hours a week from your schedule. It’d still be insanely demanding but at least you’d have a shot of doing well, not being stretched thin, and having enough sleep.
(Keep in mind that 100 hours is the upper end of what Finance/IB people do, and the reason for the very high turn out in that profession because most can’t stand it. You want to start college in good enough shape to be able to give it your all, not completely rinsed out from a crazy HS schedule).