Internal VIP to Internal VIP

I'm not sure you want an actual internal virtual server:

https://support.f5.com/csp/article/K15819

It's pretty easy to target another virtual server on a different BigIP, but there are definite limitations when both Virtual Servers live on the same BigIP. You would need to use an iRule to redirect traffic to the second virtual server:

https://support.f5.com/csp/article/K10379

It might be better to have a virtual server listening on 443 and simply configure your pool members on port 5001 and go directly to the back end servers. As the BigIP is a full proxy it will simply initiate the back end connections on the new port. I can think of very few instances where you would actually need to have the second virtual server.