Is there any way to expose blueprint's variable to the Details panel as a button ?

There is no such option in your documentations :

And it could be handy (snap to, store location etc… ).

What i do now is : make a boll editable, making a branch with Tick input and once the bool is true it passes the branch and turn it into false and then it keeps on going to the next scheduled nodes .

So when i click it on the details panel, it blink and keeps the “false” state. So in generally, it activates as a button, but looks wierd :S

That trick is used by some of the people around the office as well. I agree it is a bit hacky. I believe there is a task to be able to expose events as buttons in the Details panel which should give you what you want. I’m not sure exactly when it will be completed though.