Your problem does not seem to be related to JSON. I get the same without using JSON: 
$ perl -E '
 use utf8;
 use Data::Dumper;
 my $data = qq( { "cat" : "text – abcd" } );
 print Dumper($data);
 '
$VAR1 = " { \"cat\" : \"text \x{2013} abcd\" } ";

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If I do not use Data::Dumper, I obtain this: 

$ perl -E 'use utf8;
 my $data = qq( { "cat" : "text – abcd" } );
 say $data
 '
Wide character in say at -e line 4.
 { "cat" : "text – abcd" }

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i.e. a warning but the right output. As previously mentioned by Corion, it is a feature of Data::Dumper to display the UTF-8 escape sequences.

Using binmode, as I already told you several days ago in an answer to your previous post with the same content, I no longer have any warning: 

$ perl -E 'use utf8;
 my $data = qq( { "cat" : "text – abcd" } );
 binmode STDOUT, ":utf8";
 say $data;
 '
 { "cat" : "text – abcd" }

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Have you tried binmode?

In reply to Re: malformed UTF-8 character in JSON string in perl by Laurent_R
in thread malformed UTF-8 character in JSON string in perl by Yllar

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