Both oppo and Huawei phones use microUSB plugs, so chargers can be universal; However, with non-original charging for the mobile phone, the output voltage and current are not stable, which affects the life of the mobile phone and the battery.
The lithium battery of the mobile phone has a replay number, so it is not long-term use, it is harmless to use once in a while, but if it is often used, it is still not recommended. This mismatched fast charging scheme is still used together there are many security risks!
The charger can be universal as long as it has the same socket.