Multiple ASM policy applied on Virtual Server

You can apply the ASM policy in your irule when you select the pool. You'll want to enable the policy for the pools that need it and disable it on the pools that dont.

https://devcentral.f5.com/s/question/0D51T00006i7jvy/apply-asm-policy-through-irule

Your code should look something like this:

when HTTP_REQUEST {

   switch [string tolower [HTTP::host]] {

      a.test.ae {

           pool a_test_Pool1

ASM::enable "/Common/<asm Policy name>"}

      b.test.ae {

           pool b_test_Pool1

ASM::disable}

       }

   }