use Data::Dumper;

my %h = (
    Flinstones => {
                Dad => "Fred",
                Mom => "Wilma",
                Kid => "Pebbles",
                Pet => "Dino"
    },
    Simpsons => {
                Dad => "Homer",
                Mom => "Marge",
                Kid => "Bart",
                Pet => "Santas_Little_helper"
    });

my @desc = ("Dad", "Mom", "Kid", "Pet");
@{$h{TEST}}{@desc} = ("Mr", "Mrs", "baby", "none");

print Dumper \%h;
__END__
$VAR1 = { 
          'TEST' => { 
                      'Kid' => 'baby',
                      'Pet' => 'none',
                      'Mom' => 'Mrs',
                      'Dad' => 'Mr'
                    },
          'Simpsons' => { 
                          'Kid' => 'Bart',
                          'Pet' => 'Santas_Little_helper',
                          'Mom' => 'Marge',
                          'Dad' => 'Homer'
                        },
          'Flinstones' => { 
                            'Kid' => 'Pebbles',
                            'Pet' => 'Dino',
                            'Mom' => 'Wilma',
                            'Dad' => 'Fred'
                          }
        };
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