how to use mcu to remote updata cpld? how to relalize?

Hi,

May I know what is the purpose to write .pof to QSPI? The reason is that you are not able to use the .pof stored in QPSI to configure the Max 10 device.

For the design that does not require Nios, you may also try https://fpgacloud.intel.com/devstore/platform/17.1std.1/Standard/i2c-remote-system-update-example/ design example.