Is there a specific reason you want to stay in that state? I am no expert but I think the whole idea of a state machine is that you must change state to achieve a change of behavior, apart from some exceptions which I cant think of now.
If you want to keep all the behavior that is in that state, but change that one action. Copy and paste that state and then make the changes to the action(such as delete it) in the duplicate state. Transition between the states whenever you need the change to be implemented.
You can even do the sending of the transition from another fsm by using global events and 'send event' action.
I think this should really work fine in most circumstances, but if you explain why it would not work in your case, maybe it would help in finding a work-around your issue (or at least teach me something about what circumstances would require this).
(Also I know nothing about writing code, but maybe a script could do such a thing- or a new action- if one does not exist somewhere out there already...)
Also I am not at my computer to try this, but you really got me wondering what happens if you use 'set property' on an FSM...
Hope that helps, good luck with it!
(Edit: also I think this post makes me a' junior playmaker'. Yippeee me!- sorry to steal any limelight)