Cashflow Statement (Direct) and Cashflow Statement (Indirect) both report on the historical movement of actual cash in and out of an organisation for a specified period. Both versions of the Cashflow Statement report for the value of GST in the same way.
Income and Expense amounts are reported net of GST, as in the P&L and Balance Sheet reports, then the net movement in the GST account/s are reported in the Cashflow from Financing Activities section for the period of the report. This may be an inflow or outflow depending on the period and the transactions recorded.