How the 9-20 EMA crossover strateg Works The 9-20 EMA crossover strategy is a common trading technique used to identify potential trend reversals or trend continuation in financial markets 9-period EMA (short-term) 20-period EMA (longer-term) Bullish Signal (Buy) The 9 EMA crosses above the 20 EMA → Indicates an uptrend. Bearish Signal (Sell/Short) The 9 EMA crosses below the 20 EMA → Indicates a downtrend.