Many thanks for your efforts

I added a test suggested by kwaping above.

#!/usr/bin/perl

use strict;
use warnings;
 
my $str = q|cat’s|;
printit($str, 'original');
 
(my $str1 = $str) =~ s/\x092/'/;
printit($str1, 'hex only two nybbles');
 
(my $str2 = $str) =~ s/\x92/'/;
printit($str2, 'seems good here');
 
(my $str3 = $str) =~ s/\x{092}/'/;
printit($str3, 'seems good here');
 
(my $str4 = $str) =~ tr/\x{092}/'/d;
printit($str4, 'seems good here');

(my $str5 = $str) =~ s/’/'/;
printit($str5, 'added');
 
sub printit {
        my ($v, $msg) = @_;
        my $h = unpack "H*", $v;
        $h =~ s/(..)/0x$1 /g;
        print "$h\t$v\t$msg\n";
}

__END__

0x63 0x61 0x74 0xe2 0x80 0x99 0x73     cat’s    original
0x63 0x61 0x74 0xe2 0x80 0x99 0x73     cat’s    hex only two nybbles
0x63 0x61 0x74 0xe2 0x80 0x99 0x73     cat’s    seems good here
0x63 0x61 0x74 0xe2 0x80 0x99 0x73     cat’s    seems good here
0x63 0x61 0x74 0xe2 0x80 0x99 0x73     cat’s    seems good here
0x63 0x61 0x74 0x27 0x73     cat's    added
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