And now using the Set::Scalar module.

use Modern::Perl;
use Set::Scalar;

my $first_word  = 'CHARLIE ROOT';
my $second_word = 'HARRY NODE';

my $first  = Set::Scalar->new( split //, $first_word );
my $second = Set::Scalar->new( split //, $second_word );

say $first - $second;    # difference between $first and $second
say $second - $first;    # difference between $second and $first

say $first % $second;    # symmetric difference
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Output:

(C I L T)
(D N Y)
(C D I L N T Y)
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