use strict;
use warnings;

use XML::LibXML qw( );

my $parser = XML::LibXML->new();
my $doc    = $parser->parse_file($ARGV[0]);
my $root   = $doc->documentElement();

for my $node ($root->findnodes('//image[@scope="local"]')) {
   $node->removeAttribute('scope');
}

binmode STDOUT;
print $doc->toString();
[download]

I'm not even gonna try an XML::Simple solution.

I was curious why you binmode STDOUT in your code (and in your other example) - is it to ensure you have UNIX line endings (and not CRLFs) in the output if Perl is running on Windows?

For starters, XML is a binary format. binmode definitely won't hurt anything.

binmode doesn't just disable :crlf; it disables any :encoding too.

You probably should always use binmode or equivalent (e.g. use open), either to remove layers* when you want to ensure the bytes are unmolested*, or to add some when you want to output text.

* — These may be added via $ENV{PERLIO}, via -C, or by Perl itself as the case is for :crlf on Windows.