my $escape       = qr/(?<!\\)\\/;
my $meta_char    = qr/(?<!$escape)[?*]/;

no warnings 'qw';
my %meta = qw(
    ? #
    * ?
);

my $result = my $string = 't?e\\\\xt\\\\* with e\\scapes\\*';
$result =~ s/($meta_char)/$meta{ $1}/g;
$result =~ s/$escape(.)/$1/gs or die;

print "$string\n";
print "$result\n";