The EgressIP can be configured on additional network interfaces in an OCP 4 cluster which is deployed as BareMetal UPI/IPI only as per the below documentation. It's not supported in any other installation type such as vSphere IPI/UPI, etc.

--> https://docs.openshift.com/container-platform/4.17/networking/ovn_kubernetes_network_provider/configuring-egress-ips-ovn.html#:~:text=OpenShift%20Container%20Platform%20is%20installed%20on%20a%20bare%20metal%20cluster.%20This%20feature%20is%20disabled%20within%20cloud%20or%20hypervisor%20environments.

This feature is very critical considering that in case of any other environment such as vSphere if primary node network range gets exhausted (in terms of IP addresses) then there's no way to use EgressIP.