If the All For One in prison is a clone then how would it be revealed that the All For One in prison is a clone and what reason did All For One need to use a clone on his fight against All Might? Also what Star Wars parallel are we talking about the one involving Queen Amelia or another Star Wars parallel.
I don't know for sure that All for One is prison is a clone or how exactly that would be revealed. I think we'll have to wait to see exactly what is going on with the Nomu situation. I just feel like there is a conspiracy going on and someone else is out there possibly with the exact same quirk as one for all.
I was worried going into detail overanalyzing what may be very hollow references to Star Wars in the show could go a bit off topic but I'll try to explain...
"Begun the clone war has". Kamino Ward takes its name from the birthplace of the Clone Troopers who would make up the Grand Army of the Republic. They go on to fight in a proxy war led by the Jedi as their generals. As this "war" dragged on many citizens within the Republic saw the Jedi as a source of its corruption. The Jedi, after all, are supposed to protect the people, not go off fighting a war that is bankrupting the republic and making their lives at home more miserable. That's not far off from what we've seen going on with Hero society and the way the citizens are viewing them.