Based on my personal experience I will say these are my top 5 forex brokers in Nigeria:
1. AvaTrade
Pros: Fixed spread, Good customer support, Advanced trading software
Cons: High minimum deposit of $100, No Naira account currency
2. Tickmill
Pros: Execution speed, Platform stability, MT5 support kits
Cons: No Naira account currency, High minimum deposit of $100
3. HF Markets
Pros: Naira account currency, HFM Wallet, Customer support, Stable & transparent spread
Cons: Platform stability, High spread
4. FxPro
Pros: Naira account, FxPro Wallet, Platform stability
Cons: High spread, Customer support
5. Exness
Pros: Naira account, Platforms
Cons: Spread is not transparent, Customer support is poor