## instead of this:

open( my $fh, ">:raw:encoding(ucs2le):crlf", "testa.plp" );
print $fh "\N{CARRIAGE RETURN}\N{LINE FEED}";
close $fh;

## you want either this:

open( my $fh, ">:raw:encoding(ucs2le)", "testb.plp" );
print $fh "\N{CARRIAGE RETURN}\N{LINE FEED}";
close $fh;

## or this:

open( my $fh, ">:raw:encoding(ucs2le):crlf", "testc.plp" );
print $fh "\N{LINE FEED}";  # :crlf adds CARRIAGE RETURN for you
close $fh;