internet traffic egress load balancing for https

F5 has an entire product for this sort of SSL examination and routing - SSL Orchestrator

Trying to do this in an irule is complex and difficult, because you need to delay the server-side binding until the ClientHello has been sent and examined, and then pass the ClientHello through.

There are some irules that examine SNI headers to make decisions - have a search.

But you may find it easier to consider a ready-made and complete product that does what you require, and more.