It depends on which mode you are using. In the profile mode SSL inspection is a profile and can be selectively used in each policy. but in the NGFW mode there is no such function. The SSL inspection is selected under system settings and will be applied to the entire rule base. You cannot disable SSL inspection in the ngfw mode it has to be selected to be able to use the firewall in NGFW mode.
Your are confusing application and session layer. So no , not directly. As listed earlier application control IDs based on application signatures , protocol decoding or fingerprints or a combination of all three. So we can id applications no matter where the service runs at.
E.g HTTP APP-ID will id traffic base on the application Hyper Text Markup, so it will expect and id patterns for HTTP and would known the different from a FTP or Telnet or even something near similar like XML.
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