SQL Server 2019

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CREATE TABLE Data (
    User_ID INT,
    Credit_Account VARCHAR(100),
    Debit_Account VARCHAR(100),
    AMOUNT NUMERIC(19,4)
)
INSERT Data
VALUES    
    ('18595', 'PKR1000100013010', 'PKR1000023233010', '1364500'),
    ('16133', 'PKR1616100013001', '125450528', '1826'),
    ('16387', 'PL52008', '130984886', '4560'),
    ('18768', 'PKR1007000010025', 'PL64084', '4000'),
    ('18540', '131014988', '131013728', '159092'),
    ('18386', '105090145', 'PKR1000100013010', '167079')

SELECT
    C.Account,
    SUM(C.Credit_Amount) AS Total_Credit_Amount,
    SUM(C.Debit_Amount) AS Total_Debit_Amount
FROM Data D
CROSS APPLY (
    VALUES
        (D.Credit_Account, D.AMOUNT, 0),
        (D.Debit_Account, 0, D.AMOUNT)
) C(Account, Credit_Amount, Debit_Amount)
GROUP BY C.Account

SELECT
    C.Account,
    SUM(C.Credit_Amount) AS Total_Credit_Amount,
    SUM(C.Debit_Amount) AS Total_Debit_Amount
FROM Data D
CROSS APPLY (
    VALUES
        (D.Credit_Account, D.AMOUNT, NULL),
        (D.Debit_Account, NULL, D.AMOUNT)
) C(Account, Credit_Amount, Debit_Amount)
GROUP BY C.Account

Account	Total_Credit_Amount	Total_Debit_Amount
105090145	167079.0000	0.0000
125450528	0.0000	1826.0000
130984886	0.0000	4560.0000
131013728	0.0000	159092.0000
131014988	159092.0000	0.0000
PKR1000023233010	0.0000	1364500.0000
PKR1000100013010	1364500.0000	167079.0000
PKR1007000010025	4000.0000	0.0000
PKR1616100013001	1826.0000	0.0000
PL52008	4560.0000	0.0000
PL64084	0.0000	4000.0000

Account	Total_Credit_Amount	Total_Debit_Amount
105090145	167079.0000	null
125450528	null	1826.0000
130984886	null	4560.0000
131013728	null	159092.0000
131014988	159092.0000	null
PKR1000023233010	null	1364500.0000
PKR1000100013010	1364500.0000	167079.0000
PKR1007000010025	4000.0000	null
PKR1616100013001	1826.0000	null
PL52008	4560.0000	null
PL64084	null	4000.0000

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