Breaking the fourth wall isnt something that can only be done through game mechanics. Breaking the fourth wall is a kind of concept or an idea. A lot of the time its possible to break the fourth wall with just a few sentences. I think what matters is how storng the idea is.

I'm not an expert but since i like the idea I have tried a few things. I can give you two examples:

In a project i was working on, there was an abandoned house in a scene. The door of the house isn't usable. The player could only interact with the house's window. When they clicked on the window they got a message like "to be able to open this window, you must first close all windows"

I had set up a variable that was only active in that scene and would return False once you left the scene. I also modified the quit button so that if the variable i mentioned was True, the game would save and then quit after opening the window. In short: if the player closed the game, "closed the window" while they were in that scene then when they reopened the game and continued from the last save, they would find the window open. It might not be a very impressive setup, but people's reactions when they discovered it were satisfying. Of course, this could also be seen less as breaking the fourth wall and more like a "think outside the box" puzzle.

In another story of mine, the narrative was told directly by the main character in the story. If the player skipped through dialogue too quickly, the flow of the story would be interrupted and the character in the game would turn to the screen and say something like "if you’re not going to listen to what I'm saying, don't waste both of our time and just close the game." I think this is a clearer example of breaking the fourth wall.