Maybe can do it using this https://github.com/NodeBB/NodeBB/blob/master/src/routes/index.js#L110.
Not sure if anyone tried remounting admin to a different url
Administrators group doesn't show for category privileges
I have an admins-only section of my forum, and it seems that the administrators group is not an option when configuring privileges for a category. Is this a bug?
In the meantime, I created a "Site Administrators" group and can manually assign administrators to that group, which CAN be used when configuring privileges.