SQL Server 2022

By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.

CREATE TABLE [RiskTable](
    [ReqID] [int] NOT NULL,
    [ModuleName] [nvarchar](50) NULL,
    [CreatedDate] [datetime2](7) NULL,
    [AssociatedRisk] [nvarchar](50) NULL
);

insert into [RiskTable](ReqID,ModuleName,AssociatedRisk,CreatedDate) values
(1,'IDP',	'High',	'2022-12-18 00:00:00.0000000'),
(2,'Saa',	'High',	'2023-01-02 00:00:00.0000000'),
(3,'Saa',	'Medium',	'2023-01-07 00:00:00.0000000'),
(4,'Saa',	'Critical',	'2023-01-29 00:00:00.0000000'),
(5,'Saa',	'Low',	'2023-02-05 00:00:00.0000000'),
(6,'Saa',	'Low',	'2023-02-07 00:00:00.0000000'),
(7,'EEE',	'Critical',	'2023-03-09 00:00:00.0000000'),
(8,'Info',	'Low',	'2023-04-08 00:00:00.0000000'),
(9,'IDP',	'High',	'2023-04-28 00:00:00.0000000'),
(10,'IDP',	'Medium',	'2023-05-08 00:00:00.0000000');
10 rows affected

CREATE PROCEDURE Month_base_global
                @model varchar(20),   
                @p_start_date date,
                @p_end_date date
AS
BEGIN
DECLARE @start_date date;
DECLARE @end_date date;
    SET @start_date = @p_start_date ;
    SET @end_date = @p_end_date ;
    IF (@p_start_date IS NULL)
    BEGIN
       SET @start_date = '1970-01-01';
    END

    IF (@p_end_date IS NULL)
    BEGIN
       SET @end_date = '2030-12-31';
    END
      
    IF @model = 'ALL'
        BEGIN
          SELECT 'ALL' as [Module], ac.[Month], ac.AssociatedRisk as Risk, count(ri.ModuleName) as   'Total risks'
        FROM (
          SELECT DISTINCT convert(varchar(7), r.CreatedDate, 126) as [month], a.AssociatedRisk,  m.ModuleName
          FROM RiskTable r
          FULL OUTER JOIN (
            SELECT DISTINCT AssociatedRisk
            FROM RiskTable
          ) as a on a.AssociatedRisk is not null
          FULL OUTER JOIN (
             SELECT DISTINCT ModuleName
             FROM RiskTable
          ) as m on m.ModuleName is not null
          WHERE (r.CreatedDate) between (@start_date) and (@end_date) 
        ) as ac
        LEFT JOIN RiskTable ri on ac.[month] = convert(varchar(7), ri.CreatedDate, 126)
                               and ac.AssociatedRisk = ri.AssociatedRisk
                               and ac.ModuleName = ri.ModuleName
        GROUP BY ac.[month], ac.AssociatedRisk
        ORDER BY ac.[month], ac.AssociatedRisk desc
    END
    ELSE
        BEGIN
        SELECT @model as [Module], ac.[Month], ac.AssociatedRisk as Risk, count(ri.ModuleName) as 'Total risks'
        FROM (
          SELECT DISTINCT convert(varchar(7), r.CreatedDate, 126) as [month], a.AssociatedRisk, m.ModuleName
          FROM RiskTable r
          FULL OUTER JOIN (
            SELECT DISTINCT AssociatedRisk
            FROM RiskTable
          ) as a on a.AssociatedRisk is not null
          FULL OUTER JOIN (
             SELECT DISTINCT ModuleName
             FROM RiskTable
          ) as m on m.ModuleName = @model
            WHERE r.CreatedDate between DATEADD(mm, DATEDIFF(mm, 0, @start_date), 0) and eomonth(@end_date)
        ) as ac
        LEFT JOIN RiskTable ri on ac.[month] = convert(varchar(7), ri.CreatedDate, 126)
                               and ac.AssociatedRisk = ri.AssociatedRisk
                               and ac.ModuleName = ri.ModuleName
        GROUP BY ac.ModuleName, ac.[month], ac.AssociatedRisk
        ORDER BY ac.[month], ac.AssociatedRisk desc
    END
END
Exec Month_base_global 'Saa' , NULL, NULL


Module
Month
Risk
Total risks


Saa
2022-12
Medium
0

Saa
2022-12
Low
0

Saa
2022-12
High
0

Saa
2022-12
Critical
0

Saa
2023-01
Medium
1

Saa
2023-01
Low
0

Saa
2023-01
High
1

Saa
2023-01
Critical
1

Saa
2023-02
Medium
0

Saa
2023-02
Low
2

Saa
2023-02
High
0

Saa
2023-02
Critical
0

Saa
2023-03
Medium
0

Saa
2023-03
Low
0

Saa
2023-03
High
0

Saa
2023-03
Critical
0

Saa
2023-04
Medium
0

Saa
2023-04
Low
0

Saa
2023-04
High
0

Saa
2023-04
Critical
0

Saa
2023-05
Medium
0

Saa
2023-05
Low
0

Saa
2023-05
High
0

Saa
2023-05
Critical
0


Warning: Null value is eliminated by an aggregate or other SET operation.

Module	Month	Risk	Total risks
Saa	2022-12	Medium	0
Saa	2022-12	Low	0
Saa	2022-12	High	0
Saa	2022-12	Critical	0
Saa	2023-01	Medium	1
Saa	2023-01	Low	0
Saa	2023-01	High	1
Saa	2023-01	Critical	1
Saa	2023-02	Medium	0
Saa	2023-02	Low	2
Saa	2023-02	High	0
Saa	2023-02	Critical	0
Saa	2023-03	Medium	0
Saa	2023-03	Low	0
Saa	2023-03	High	0
Saa	2023-03	Critical	0
Saa	2023-04	Medium	0
Saa	2023-04	Low	0
Saa	2023-04	High	0
Saa	2023-04	Critical	0
Saa	2023-05	Medium	0
Saa	2023-05	Low	0
Saa	2023-05	High	0
Saa	2023-05	Critical	0