TDS amount is to be calculated by grossing up (For e.g. Invoice amount is 100, TDS rate is 15%, So TDS will be deducted by grossing up amount to 100/85*100 = 117.65). This tax amount will be paid by the client who is responsible for paying the invoice amount to the foreign vendor. Hence, TDS amount is not to be deducted from the Invoice amount but paid by the client.

Since we don't have the Grossing up functionality in the System, we should post the Adjustment entry from General journal form for extra amount of invoice.
So this functionality should be incorporate so that Manual intervention will not be there and calculation will happen correctly.