stateless firewall acl return traffic?

I am working with a cisco router and need to implement some acls. I have up till this point, only worked with stateful firewalls.

Before I started messing around with this, I wanted to confirm something.

I understand that with stateful firewalls, any outbound traffic is generally whitelisted so it can return by default since the firewall is aware of the state of a connection.

My understanding is with stateless I would need to create a rule for both directions. Is this correct?