Use this:

use threads;
use threads::shared;
use Data::Dumper;

sub clone {
    my $ref = shift;
    my $type = ref $ref;
    if( $type eq 'HASH' ) {
        return { map clone( $_ ), %{ $ref } };
    }
    elsif( $type eq 'ARRAY' ) {
        return [ map clone( $_ ),@{ $ref } ];
    }
    elsif( $type eq 'REF' ) {
        return \ clone( $$ref );
    }
    else {
        return $ref;
    }
}


my $x :shared = shared_clone({
    a => 'Foo',
    b => 'Bar'
});

my $z = clone( $x );
print Dumper( $z );
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