Using XML::XSH2, a wrapper around XML::LibXML:

#!/usr/bin/perl
use strict;
use warnings;

use XML::XSH2;
use Data::Dumper;

xsh << 'end.';
    open 1.xml ;
    $h := hash ../../../Seller/@sellerIdFromProvider
          /DataFeed/SellerInformation/TaxableLocationsCollection/Taxab
+leLocation/@locationValue ;
end.

$_ = [ map $_->getValue, @$_ ] for values %$XML::XSH2::Map::h;   # Con
+vert attributes to strings.
print Dumper($XML::XSH2::Map::h);
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Update: show how to convert from XML::LibXML::Attribute objects to strings.