If there's an option for "if key "x" is pressed" then it should be possible.
Say yu have the 4 arrows. Make them change a variable called let's say specialAttack.
Up = add 1
Down = Add 10
Left = Add 50
Right = Add 250
The reason I say these numbers, is that it'll be unlikely for someone to push up ten times instead of down, whereas a simple 1-2-3-4 thing, it would be fully possible to make a stuff up and continue the move.
Then you can make it if Variable = 261 (Right, down, Up), do move.
This would be primitive of course, and contain no special order. But hopefully it'll get you thinking of how to do it.
Also you'd need a failsafe. Maybe upon 8 Key presses = false move? Well, hope it helps.
Note: This sytem is also used for Zell's Limit in FF8.