Tumbleweed 20191124, in my autoyast post install no grub.cfg is generated:

+ grub2-mkconfig -o /boot/grub2/grub.cfg
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-5.3.12-1-default
Found initrd image: /boot/initrd-5.3.12-1-default
Found hypervisor: /boot/xen-4.13.0_02-1.gz
Found linux image: /boot/vmlinuz-5.3.12-1-default
Found initrd image: /boot/initrd-5.3.12-1-default
awk: cmd. line:18: warning: regexp escape sequence `\"' is not a known regexp
operator
awk: cmd. line:18: warning: regexp escape sequence `\"' is not a known regexp
operator
cp: -r not specified; omitting directory '/boot/'

bash -x $(type -P grub2-mkconfig) -o /boot/grub2/grub.cfg
...
+ echo '### BEGIN /etc/grub.d/20_linux_xen ###'
+ /etc/grub.d/20_linux_xen
Found hypervisor: /boot/xen-4.13.0_02-1.gz
Found linux image: /boot/vmlinuz-5.3.12-1-default
Found initrd image: /boot/initrd-5.3.12-1-default
awk: cmd. line:18: warning: regexp escape sequence `\"' is not a known regexp
operator
awk: cmd. line:18: warning: regexp escape sequence `\"' is not a known regexp
operator
cp: -r not specified; omitting directory '/boot/'