It’s definitely there:
root@zfs:~# modprobe f2fs
root@zfs:~# lsmod | grep f2fs
f2fs 823296 0
lz4hc_compress 24576 1 f2fs
lz4_compress 36864 1 f2fs
zstd_compress 299008 1 f2fs
root@zfs:~# cat /etc/rocky-release
Rocky Linux release 9.5 (Blue Onyx)
root@zfs:~# uname -r
6.1.135-1.el9.elrepo.x86_64