Is it safe to switch to SELinux from AppArmor on Ubuntu host machine?

I am trying out CentOS containers. Noticed that even if SELINUX config value is set to enabled, getenforce returns disabled.

I read somewhere that it is probably because of SELinux is not installed on Ubuntu host (AppArmor is)

Is it safe to switch to SELinux without impacting the existing host setup and Ubuntu containers and later revert?

Is following the right setting for unconfined equivalent to AppArmor?
lxc.se_context = unconfined_u:unconfined_r:lxc_t:s0-s0:c0.c1023

Please let know your thoughts.