Higher-Level Course Validation and Overload in Engineering Major

Many insights are provided that lead me to believe both are NOT impossible, but likely NOT probable. Also that USNA or any academy may not be the best choice. Many postings in here about the medical option and how long it takes to get through it after your 9 yr academy + service commitment. Then you could start med school, at approximately age 27 at the earliest. Stuff like that. Make sure you research it.

Seems like you have great ambition and goals. Whatever you decide to do I wish you all the best.
You won't be doing massive research as a Navy doctor. You will be a Doctor, who if lucky, will get to spend a tour doing research, if selected maybe once in their career. The Navy needs doctors fixing and keeping their Sailors and Marines healthy (and their families). If you really want to do research, then being a civilian doctor is going to be much more flexible to what you want to pursue.
While USNA does produce a VERY few doctors, I wouldn't suggest going to USNA if your goal is to become a doctor and nothing but a doctor.

Validating classes at USNA only works if you receive an appointment. That should be your focus at this point.
Keep in mind you will very likely not be authorized to overload first semester Plebe year (i.e. validations can slide next courses in sequence, but not able to add additional courseload).

Performance anywhere outside of USNA does not guarantee success at USNA. Whatever you want to do, you will will have to cram into 3.5 years.

To recap, you want to dual-major chemistry with biology course requirements and an engineering major, and do a research program like Trident Scholars on the side--missed that the first read-through.

I won't say it's definitely impossible, but it probably is. Even if it is, Commandant and Academic Dean will need some serious convincing, and that'll probably be after you ace first semester Plebe year. And then your plan will be to drown yourself in academic work, forget about the other ECAs, PRODEV, or leadership opportunities within the Brigade.

Also, USNA is great and all, but if you want to do research, USNA is not the place. The research you do will mostly be for your capstone project. Trident Scholars will tackle something more substantial, but it's not comparable to the opportunities available at a real research university (which USNA is not).
Why not shoot for a top civilian engineering/STEM school and look into the NUPOC program, which doesn’t involve ROTC-like classes, but gets a big chunk of college paid for, lets you STEM out to your heart’s content, gives you a commission as a Navy nuclear officer. Serve your time honorably, complete eligibility for the VA Post 9/11 GI Bill, and get medical school paid for once you are a civilian again. Then you will have served in the Navy, done serious STEM, and can cheerfully pursue a MD-PhD program, perhaps in nuclear medicine, whatever you wish.

From the Ga Tech website: