Fitz. Coz

Time travel machine.

copy that

Stark.

Well according to the in cannon, The Wakanda Files, the person that Shuri seems to think is the smartest is Hank Pym

https://screenrant.com/mcu-hank-pym-smartest-character-not-shuri-confirmed/

Shuri seems like a fangirl as she discusses Hank Pym's quantum technology. At one point she says:

"There are no words to express the envy I feel toward Lang and Pym for their time in the Quantum Realm. Pym's quantum mechanics research is exciting. The possibilities for transportation improvement...

How did Pym get his hands on an EM-drive that works outside of a vacuum chamber? We have been attempted to create a Mach-effect thrust without a reactionary force for months, maybe years. It defies the laws of physics. Unless the Quantum Realm acts as a vacuum chamber? That would prove Heisenberg's principle of a quantum vacuum. So many questions. We must talk with Pym. Immediately."

Also, Shuri comments on the superiority of the Pym Particle for strength and speed over Stark's tech.

Hard to call. Maybe Rocket. Maybe Thanos. Maybe Shuri. Maybe Tony.

So many

Thor

Shuri, definitely. She's a tech wizard!