UPDATE: Except I didn't do the cartesian product... but anyways...

use strict;
use warnings;
use Data::Dumper;

my $AoH_show_characters = [];

my $HoA_show_characters = {
            flintstones        => [ "fred", "barney" ],
            jetsons            => [ "george", "jane"],
      };
      
foreach my $show (keys %$HoA_show_characters) {
    foreach my $character ( @{ $HoA_show_characters->{$show} }  ) {
        push @$AoH_show_characters, ( { $show => $character } );
    }        
}

print Dumper($AoH_show_characters);
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