G'day tel2,

Here's my offering. It just uses length and substr. There's no: concatenation; splitting strings into lists; regexes; or modules to load.

#!/usr/bin/env perl -l

use strict;
use warnings;

print zip("ABCDEFGHIJ", "abcde");

sub zip {
    my ($str1, $str2) = @_;

    for (0 .. length $str2) {
        substr $str1, $_ * 2 + 1, 0, substr $str2, $_, 1;
    }

    return $str1;
}
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Output:

AaBbCcDdEeFGHIJ
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