I'm pretty sure Huawei is saving the 5nm chip for launch later this year with the Mate 70. Launching a 5nm chipset phone so close to the 7nm Mate 60 makes no marketing sense. Huawei can get away with overclocking the 7nm CPU for the P70. BUT consumers will demand much much more features for the Mate 70 launch, like for example a 5nm chip.
A new rumour from Baidu reveals the specifications of Huawei's next flagship mobile SoC known as the HiSilicon Kirin 9010. It features an 8-core CPU with custom cores, a Balong 5G modem, and an in-house ISP/NPU/GPU. Performance-wise, it trades blows with the Snapdragon 8+ Gen 1 and Dimensity 9200+.