MySQL 5.7

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create table TableOne(id int, num varchar(5));
insert into TableOne(id, num) values
(1, 'abcde'),
(2, '01234'),
(3, '56789');
                                          
create table TableTwo(id int, num varchar(5));

Records: 3  Duplicates: 0  Warnings: 0


insert into TableTwo(id, num)
select
  t.id,
  concat(
    coalesce(right(t1.num, 3), 'xxx'), 
    coalesce(left(t.num, 2), '')
  ) num
from (
  select * from TableOne
  union all
  select max(id) + 1, null from TableOne
) t left join TableOne t1
on t1.id = t.id - 1;

Records: 4  Duplicates: 0  Warnings: 0


select * from TableTwo;


id
num


2
cde01

3
23456

4
789

1
xxxab