Can we WITH x AS ( ... ) INSERT INTO y(k) SELECT * FROM x in MySQL?
Something like
insert into item
  with x as (    
    select id + 10 as id1, concat(brand,' D') as brand1 from item),
       y as (    
    select id + 20 as id1, concat(brand,' E') as brand1 from item)  
  select * from x   
  union all   
  select * from y

Yes, we can!