default or selected kernelversion does not have config value CONFIG_STAGING_EXFAT_DEFAULT_CODEPAGE.
Result is shown for kernelversion 5.8-rc2
Default codepage for exFAT
configname: CONFIG_STAGING_EXFAT_DEFAULT_CODEPAGE
Linux Kernel Configuration
└─>Device Drivers
└─>Staging drivers
└─>Default codepage for exFAT
In linux kernel since version 5.6 (release Date: 2020-03-29)
This option should be set to the codepage of your exFAT filesystems.