Maybe something like this? (Contrived example)

use warnings;
use strict;

my %hash = (
    'Bob' => {
        'best'  => 9,
        'worst' => 5
    },
    'Steve' => {
        'best'  => 5,
        'worst' => 1
    },
    'Mark' => {
        'best'  => 10,
        'worst' => 4
    },
    'Dave' => {
        'best'  => 7,
        'worst' => 3
    }
);

print "\npeople by best\n";
for my $key ( sort_by( \%hash, 'best' ) ) { print "$key\n" }

print "\npeople by worst\n";
for my $key ( sort_by( \%hash, 'worst' ) ) { print "$key\n" }

print "\nproperties\n";
for my $key ( sort_by( $hash{'Bob'}, undef ) ) { print "$key\n" }

sub sort_by {
    my ( $ref, $constant ) = @_;
    if ( defined $constant ) {
        return sort { $ref->{$b}->{$constant} <=> $ref->{$a}->{$consta
+nt} } keys %$ref;
    }
    else {
        return sort { $ref->{$b} <=> $ref->{$a} } keys %$ref;
    }
}
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