How to stop spacebar clicking things

Hello, I’m having a problem trying to disable the spacebar clicking things in my blueprint game.
The main solution in other posts is to override the functions OnKeyDown and OnKeyUp in the widgets, but I can’t do this, cause I have a custom button, child of the original button class in UE and it won’t allow overriding. All my interfaces are full of this custom buttons and are the ones being clicked if the player presses space bar, I just want that option to be disabled.
Any help or tip is welcome, thanks in advance.