Is [there] any module other than Text::Unidecode, or a method of converting these characters like ',",-,.,? to simple ASCII characters?
Why do you not want to use Text::Unidecode? It does exactly what you are requesting: 
use utf8;
use JSON;
use Encode qw(encode_utf8);
use Text::Unidecode;

my $data = qq( { "cat" : "text – abcd  “ ’ ” ‘" } );
my $json_data = encode_utf8( $data );
my $perl_hash = decode_json( $json_data );
while ( my($k,$v) = each %$perl_hash ) {
    unidecode($v);
    print "$k => $v\n";
}

[download]
Output: 
cat => text - abcd  " ' " '

[download]

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

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