Hello,
the easiest way (in Azure) is to deploy Workspace in VNET Injection mode and attach NAT Gateway to you VNET. NAT GW require Public IP.
This IP will be your static egress IP for all Cluster in for this Workspace.
Note: both NAT GW and IP Address comes with additional infrastructure cost.
There are alternatives like
- routing your outbound communication using UDR to Firewall and outbound from Firewall IP (if you don't have existing FW it will be costly)
- use Azure Load Balancer with Public IP (but it is harder to manage)