If your phone is several years old, it might use a 32-bit processor (ARMv7 or 32-bit ARMv8).
Open the app and, within the graphics settings, switch to OpenGL for better compatibility with older hardware. Tips for Optimizing 32-Bit Performance (Hot Settings)
These projects originated from a developer known as "weihuoya". The MMJ (and its successor, ) builds were designed to run on less powerful devices by cutting some emulation accuracy in favor of raw speed.
Before attempting to download third-party APKs, verify if your device can actually run the official app: Dolphin for Android: System Requirements