1. Hit
2. Goku Black
3. Majin Buu
Ultra Instinct is something not unique to the saiyans so potentially any alien race could achieve it. Though of course some characters would be more powerful with it than others.
I think each of these characters have got more than enough base power, and potential for UI to give them maybe an even bigger boost than what Goku got.
Current Hit is anywhere from Current SSB-Current SSBKKx20 level (I personally think he's current SSBKKx20 level for being able to withstand the same glare technique Jiren used to knock Goku out of SSBKKx20 but at a higher rate of fire). Hit's also got massive potential with how he was never challenged until just recently and he taps into that potential each time he improves mid-battle. Lastly being able to use his One-Hit-Kill Hax abilities automatically would be a huge benefit for Hit.
Goku Black Post Rage Boost seemed to be on the same level as Post HTC training SSB Vegeta power-wise and he could get seemingly endless zenkai boosts prior to reaching his limit and needing the rage boost against Vegeta. So it's safe to say he has fairly huge potential as well.
Lastly Majin Buu. Majin Buu reached Current Base Goku level with only a few hours of training (Slim Buu). His potential could be ridiculously high with that considered. And he may able to handle the strain of UI very well with his unique body structure.
2. Goku Black
3. Majin Buu
Ultra Instinct is something not unique to the saiyans so potentially any alien race could achieve it. Though of course some characters would be more powerful with it than others.
I think each of these characters have got more than enough base power, and potential for UI to give them maybe an even bigger boost than what Goku got.
Current Hit is anywhere from Current SSB-Current SSBKKx20 level (I personally think he's current SSBKKx20 level for being able to withstand the same glare technique Jiren used to knock Goku out of SSBKKx20 but at a higher rate of fire). Hit's also got massive potential with how he was never challenged until just recently and he taps into that potential each time he improves mid-battle. Lastly being able to use his One-Hit-Kill Hax abilities automatically would be a huge benefit for Hit.
Goku Black Post Rage Boost seemed to be on the same level as Post HTC training SSB Vegeta power-wise and he could get seemingly endless zenkai boosts prior to reaching his limit and needing the rage boost against Vegeta. So it's safe to say he has fairly huge potential as well.
Lastly Majin Buu. Majin Buu reached Current Base Goku level with only a few hours of training (Slim Buu). His potential could be ridiculously high with that considered. And he may able to handle the strain of UI very well with his unique body structure.
