#!/usr/bin/perl

use strict; # https://perlmonks.org/?node_id=11139200
use warnings;
use List::Util qw( none );
$| = 1;

my @strings;
while( @strings < 10 )
  {
  my $try = join '', map +('A' .. 'Z')[rand 26], 1 .. 5;
  if( none { ($try ^ $_) =~ tr/\0//c < 3 } @strings )
    {
    push @strings, $try;
    print "$try ";
    }
  }
print "\n";
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Sample Output

OJLGF RESJW YKHXZ CGINN RMVRS NBVJA PKZFG DHBNR JMXML QFAUY
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