Here is an SSCCE:

use strict;
use warnings;

use XML::LibXML;
use Test::More tests => 1;

my $in = '<seg><foo mid="0" mtype="seg"><g id="1">Need to export this 
+text</g></foo></seg>';
my $want = '<g id="1">Need to export this text</g>';
my $xml = XML::LibXML->load_xml (string => $in);

my $have = $xml->getElementsByTagName ('g')->shift->toString;
is ($have, $want);
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