So are you saying that you want to turn all the fans off when you pause, not just the print cooling fan (which is turned on automatically when you resume the print)? If so then the simplest option is to configure the other fans for thermostatic control, then they will only be on when needed.
You could also turn the printer off completely after pausing it (wait for the hot end to cool down before you turn the hot end fan off) and then use the resurrection facility, if you configure it first. In the last several firmware versions, the resurrect.g file is created automatically whenever you pause the print. See https://duet3d.dozuki.com/Wiki/Setting_up_to_resume_a_print_after_a_power_failure.
