If you look at the help document of the Outport block, it says the "Initial Output" property is valid when the Outport block is inside a "Conditionally Executed Subsystems (wihch include Enabled Subsystem, Triggered Subsystem, Enabled and Triggered Subsystem, Function-Call subsystem)
Also, the property is valid only when "Source of initial output value" is set to "Dialog".
Based on the above two constraints, I think you can use find_system() to find the blocks.
