default or selected kernelversion does not have config value CONFIG_NCPFS_NLS.
Result is shown for kernelversion 6.7-rc3

Use Native Language Support

configname: CONFIG_NCPFS_NLS

Linux Kernel Configuration
└─>File systems
└─>Network File Systems
└─>Use Native Language Support
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
Allows you to use codepages and I/O charsets for file name
translation between the server file system and input/output. This
may be useful, if you want to access the server with other operating
systems, e.g. Windows 95. See also NLS for more Information.

To select codepages and I/O charsets use ncpfs- or newer.