Adding VIP "networks" as connected routes

i'm not sure if i totally understand your question.

you can use VIPs on any IP address, that IP address doesn't not have to match on an interface on the F5.

the F5 does of course need an IP to route traffic to from a router or such.

but you can you have VIPs in 10.10.10.0/24 and only have an interface on 10.20.20.1, those VIPs will work if you route traffic for it to it.