Can you dump the hex values and check? (or just try code below).

If your users are entering latin-1, then you could use the Encode module to shift the script to utf8.

#!/usr/bin/perl
use strict;
use warnings;
use Encode;
use utf8;

my $code = <<"EOLATINCODE";
my \$var_with_\xE9_accent = 10;
print \"var is \$var_with_\xE9_accent\\n\";
EOLATINCODE

$code = decode('latin1', $code);
print "CODE is $code\n";
eval $code;
if ($@) {
    print "DIED: $@\n";
}
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