hm this would be more difficult then. You could use a trick.
You could for example create 2 regions, and if a unit enters, that you dont want to, you give it the order to turn back to the region before...
There are several posibilities.
You could check if the entering play is the one of your choice, and kill one single pathing blocker, after the unit passed, you restore it.
Another way would be u install only ground blockers, and if the unit entering the region is the one you want, you give it the ability "crow-form". You have to install around this area only-flight-blockers, and it would not match with flying units.
Well, there are some possibilities
Greets