This was a major challenge Nigeria's Crypto community faced which forced crypto traders to revert to the old way of buying and selling commonly known as "Peer to Peer (P2P)".
Several popular exchanges have implemented the P2P feature on their exchange. A typical example is Quidax which launched it's P2P platform weeks back.
Details can be found here :
https://blog.quidax.com/make-way-p2p-is-live-on-quidax/The problem with P2P is that you will be flooded with scammers, at least during the initial phases. When I was trading in Localbitcoins during my earlier days, I faced a lot of issues due to this. It takes a few months for a vendor to build up a good feedback score and earn a good reputation. During this time, a lot of people are going to get conned by the scammers. And the fact that cryptocurrency is in a grey area in Nigeria will make matters more complicated.
Binance could actually help a lot with that P2P transactions. Their current platform is a sure way on how people would not get scammed. People are only required to do transactions once they do their verification and set up multiple verification. They are only also required to do one account and most people are not even eligible to do transactions without going thru this sure way to confirm that the person doing that transaction is real.