SQL Server 2017

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create table Invoicetable(IN_ID varchar(100), IN_InvoiceID int)
INSERT INTO Invoicetable (IN_ID, IN_InvoiceID)
VALUES
    ('2345-BCDE-6645-1DDF', 1),
    ('2345-BCDE-6645-3DDF', 2),
    ('2345-BCDE-6645-4DDF', 3),
    ('2345-BCDE-6645-5DDF', 4),
    ('2345-BCDE-6645-6DDF', 5),
    ('2345-BCDE-6645-7DDF', 6),
    ('2345-BCDE-6645-aDDF', 7),
    ('2345-BCDE-6645-sDDF', 8),
    ('2345-BCDE-6645-dDDF', 9),
    ('2345-BCDE-6645-dDDF', 10),
    ('2345-BCDE-6645-dDDF', 11),
    ('2345-BCDE-6645-dDDF', 12);
12 rows affected

with data
  as (
select *
      ,(in_invoiceid-1)/5 as grp
      ,case when ((in_invoiceid-1)/5)%2=0 then '1' else '0' end as category
      ,dense_rank() over(partition by  case when ((in_invoiceid-1)/5)%2=0 then '1' else '0' end
                    order by in_invoiceid) as rnk
  from invoicetable a
      )
   select *
      from data a
 left join data b
        on a.rnk=b.rnk       
       and b.category=0
     where a.category=1       
   
  


IN_ID
IN_InvoiceID
grp
category
rnk
IN_ID
IN_InvoiceID
grp
category
rnk


2345-BCDE-6645-1DDF
1
0
1
1
2345-BCDE-6645-7DDF
6
1
0
1

2345-BCDE-6645-3DDF
2
0
1
2
2345-BCDE-6645-aDDF
7
1
0
2

2345-BCDE-6645-4DDF
3
0
1
3
2345-BCDE-6645-sDDF
8
1
0
3

2345-BCDE-6645-5DDF
4
0
1
4
2345-BCDE-6645-dDDF
9
1
0
4

2345-BCDE-6645-6DDF
5
0
1
5
2345-BCDE-6645-dDDF
10
1
0
5

2345-BCDE-6645-dDDF
11
2
1
6
null
null
null
null
null

2345-BCDE-6645-dDDF
12
2
1
7
null
null
null
null
null

IN_ID	IN_InvoiceID	grp	category	rnk	IN_ID	IN_InvoiceID	grp	category	rnk
2345-BCDE-6645-1DDF	1	0	1	1	2345-BCDE-6645-7DDF	6	1	0	1
2345-BCDE-6645-3DDF	2	0	1	2	2345-BCDE-6645-aDDF	7	1	0	2
2345-BCDE-6645-4DDF	3	0	1	3	2345-BCDE-6645-sDDF	8	1	0	3
2345-BCDE-6645-5DDF	4	0	1	4	2345-BCDE-6645-dDDF	9	1	0	4
2345-BCDE-6645-6DDF	5	0	1	5	2345-BCDE-6645-dDDF	10	1	0	5
2345-BCDE-6645-dDDF	11	2	1	6	null	null	null	null	null
2345-BCDE-6645-dDDF	12	2	1	7	null	null	null	null	null