MySQL function which behaves like zip function.

zip.sql

CREATE FUNCTION `zip`(_first text, _second text, _separator text, _pair_separator text) RETURNS text CHARSET utf8
BEGIN
  DECLARE _ret text;
  
  IF 0 < LENGTH(_first) THEN
    SELECT
      GROUP_CONCAT(
        CONCAT_WS(
          _pair_separator,
          REPLACE(SUBSTRING_INDEX(v.`first`, _separator, p.rownum), CONCAT(SUBSTRING_INDEX(v.`first`, _separator, p.rownum - 1), _separator), ''),
          REPLACE(SUBSTRING_INDEX(v.`second`, _separator, p.rownum), CONCAT(SUBSTRING_INDEX(v.`second`, _separator, p.rownum - 1), _separator), '')
        )
        SEPARATOR ' '
      )
    INTO
      _ret
    FROM
      ( SELECT
          _first `first`
        , _second `second`
        , LENGTH(_first) - LENGTH(REPLACE(_first, _separator, '')) + 1 `num_element`
      ) v
      INNER JOIN pivot p
        ON p.rownum <= v.num_element
    ;
  END IF;
  
  RETURN _ret;
END

requires pivot table.
mysql> select * from pivot;
+--------+
| rownum |
+--------+
| 1 |
| 2 |
| 3 |
| 4 |
| 5 |
+--------+
5 rows in set (0.01 sec)

mysql> select zip('a,b,c', '1,2,3', ',', '-');
+----------------------------------------+
| zip('a,b,c', '1,2,3', ',', '-') |
+----------------------------------------+
| a-1 b-2 c-3 |
+----------------------------------------+
1 row in set (0.01 sec)

mysql> select zip('a b c', '1 2 3', ' ', ',');
+----------------------------------------+
| zip('a b c', '1 2 3', ' ', ',') |
+----------------------------------------+
| a,1 b,2 c,3 |
+----------------------------------------+
1 row in set (0.00 sec)