CircuitPython supports external SPI/QSPI flash chips for the CIRCUITPY filesystem. Each board build is setup to support only one or a few flash chips. The chips are not identical in how they are accessed, so you can't just substitute without rebuilding. The chips that CircuitPython currently supports are listed in a GitHub repository of chip data, https://github.com/adafruit/nvm.toml, along with the settings needed for each.

The chip(s) that are supported in a particular board are specified in the mpconfigboard.mk file for that board, in the line that defines EXTERNAL_FLASH_DEVICES.  So change or add to EXTERNAL_FLASH_DEVICES if you want to use a different supported chip. We don't support a entire list of chips for each build because the table of data for all possible chips would take significant space in the CircuitPython build.

Here's an example: