I think Gaara could be a really tough opponent for Naruto in an MMA - like scenario. Gaara has great control over his sand, which could be used defensively and offensively in a fight. He's also very resilient and has a lot of experience in combat. His stoic nature would make it difficult for Naruto to read his moves and find an opening. And Gaara's determination to win is on par with Naruto's.
Sasuke could still be a tough opponent. Even though Naruto has all elemental affinities, Sasuke has his own powerful Sharingan and Rinnegan abilities. He can manipulate Amaterasu and other powerful techniques. Their rivalry would be intense as Naruto tries to use his newfound elemental powers against Sasuke's ocular powers.
Sasuke could still be a tough opponent. Even though Naruto can use all elements, Sasuke has his own powerful abilities, like his Sharingan and Rinnegan. He's very skilled in ninjutsu and genjutsu. Another tough opponent might be Madara. He has vast experience and extremely powerful jutsu. Naruto would have an advantage with all elements, but Madara's knowledge and power would make him a formidable foe.
Madara Uchiha. He is extremely powerful with his Sharingan and Rinnegan abilities. Even if Naruto is a martial arts master, Madara's vast array of jutsu and his strategic mind would make him a formidable foe. He could use his space - time ninjutsu to avoid Naruto's attacks and then counter with powerful attacks of his own.
His training routine would probably involve a lot of physical conditioning. He'd do things like intense cardio workouts to build stamina, similar to his long - distance running in the series. For strength, he might lift weights, but also use his chakra - enhanced strength training methods. And of course, he'd need to practice his combat skills constantly. He'd spar with different opponents to learn different fighting styles, just like how he learned from various ninja in the Naruto world.
It could be Sasuke. Sasuke is highly intelligent and has a great strategic mind. He would approach shogi with the same intensity as he does his ninja battles. He would be able to analyze Naruto's moves quickly and counter them effectively.
Madara Uchiha would be a formidable foe. His Sharingan abilities are second to none and his experience in battle is vast. He could easily outwit and overpower the team with his powerful jutsu and strategic mind. Plus, his connection to the Uchiha clan's history gives him an edge in understanding and countering the team's moves.
I think Broly could also be a really tough opponent. In his Legendary Super Saiyan form, he has incredible power and his rage - driven fighting style could give Goku SSJ4 a hard time in the Tournament of Power. Broly doesn't hold back and his raw power could potentially overpower Goku if he's not careful.
Sasuke could be a tough opponent. He has his own natural athleticism and competitive spirit. He would be very strategic on the football field, always looking for ways to outwit Naruto.
His toughest opponent could be Gary. Gary has always been a rival to Ash and has a strong and diverse team of Pokemon. Their battle would be intense as they both know each other's battling styles well.
Loki would also be a difficult adversary. He's very cunning and could use his tricks and illusions to try and outwit Goku. Goku would need to rely on his senses and ki to see through Loki's deceptions.