default or selected kernelversion does not have config value CONFIG_NFT_MASQ_IPV4.
Result is shown for kernelversion 6.9.9

IPv4 masquerading support for nf_tables

modulename: nft_masq_ipv4.ko

configname: CONFIG_NFT_MASQ_IPV4

Linux Kernel Configuration
└─>Networking support
└─>Networking options
└─>Network packet filtering framework (Netfilter)
└─>IP: Netfilter Configuration
└─>IPv4 masquerading support for nf_tables
In linux kernel since version 3.18 (release Date: 2014-12-07)  
This is the expression that provides IPv4 masquerading support for
nf_tables.

source code:
net/ipv4/netfilter/nft_masq_ipv4.c