Both chipsets are quite impressive. Qualcomm offers three-tier CPU arrangements, which features one semi-custom cortex- A 77 core ran at 2.84 GHz, three semi-custom Cortex A77 cores running at 2.461.
MediaTek's chipsets choose a more standard approach, using four Cortex -A77 cores at 2.6 GHz and four Cortex A55 cores at 2Ghz. Qualcomm has more OEM support than MediaTek who's devices have a short shelf life. They are also slower to upgrade compared to Qualcomm, and little research has been employed on Media Tek.
Qualcomm is more expensive than those with MediaTek SoCs. However, it introduces bold technologies such as AI processing, a better camera, voice XR, gaming experiences, and a secure location to store biometric information.