The radiation from the speaker remains the same but the response at the listening position will change depending on the distance to the walls. Most cardioid speakers have high rear rejection so the wall behind the speaker is less of an issue, but still wide horizontal directivity so close side walls are a problem as they are for any speaker without very high horizontal directivity.
In a very compromised position absorption to the sides and cardioid to help with the rear wall is a good option to deal with boundary effects.
Simulations can help ball park the effects based on distances.
https://www.audiosciencereview.com/forum/index.php?threads/dutch-dutch-8c-review.21016/post-989007
https://www.audiosciencereview.com/forum/index.php?threads/dutch-dutch-8c-review.21016/post-990590
In a very compromised position absorption to the sides and cardioid to help with the rear wall is a good option to deal with boundary effects.
Simulations can help ball park the effects based on distances.
https://www.audiosciencereview.com/forum/index.php?threads/dutch-dutch-8c-review.21016/post-989007
https://www.audiosciencereview.com/forum/index.php?threads/dutch-dutch-8c-review.21016/post-990590