Here are the rules that I have currently come up with:
Ok, so I was thinking of something like an Espionage SRG, where once every year (so they have to chose between spring and autumn) they can get their secret service or spies to perform an action. I was thinking of three different possible actions.

1) Counter-espionage
2) Sabotage
3) Implicate.

The desired action is sent to the GM. With Sabotage, you can select any unit on the board (eg Italian player chooses to sabotage the German army in Silesia, and if the owning country has not chosen to do counter espionage that turn then the selected unit is made to hold that turn rather than whatever other order was selected. (eg Germany had their secret service do nothing that turn, so their unit in Silesia must hold that turn rather than doing whatever it was previously ordered to do [Scenario 1]).

Had the German player instead opted to go with counter-espionage (CE) that turn, then the unit in Silesia would have done whatever it was originally ordered to do as CE blocks other country's actions against the player. [Scenario 2]

At the beginning of each turn a report is either sent to each player or put in the public chat box as to whether spy actions succeeded or failed. If it succeeded (like in the first scenario) then just the action and effect is reported (Someone sabotaged the army in Silesia so it had to hold), whereas if the controlling country had selected CE (like in Scenario 2) then the country name would also be put in the report (Italy attempted to sabotage the army in Silesia but failed.)

Finally, implicate is used to make it look like someone else used a plot (France implicates Italy, making it look like Italy attempted and failed to sabotage the German army in Silesia.) If the country on the receiving end (Germany) were to use CE, it would reveal this fake plot as if it were a real plot and would give a corresponding item in the report (Italy attempted and failed to sabotage the army in Silesia). If the target (Germany) didn't use CE, nothing would happen.

Those are the rules so far, but I have been informed by a higher power that it is not really possible to alter the orders at process time, so instead I was wondering if for example the player owning the unit (Germany) is told that the unit in Silesia must hold for the next turn.

Any ideas/thoughts/questions?