So, since 4.11 i can no longer run my project in debugGame through visual studio because “WorldGridMaterial contains editor only data”, the problem there is, over 300 assets reference that material apparently including default content from the engine.
Is there an easy fix to this?
Delete the Material, you should be asked if you want to replace references, just point to your new material.
Obviously backup your projects beforehand
Might not be exactly what you’re looking for, but if you just want to change materials on a bunch of brushes at the same time:
SHIFT + S to select all surfaces (or Right Click > Select > Select all Surfaces), and then apply the material you want.
You could also select the brushes you want, then press SHIFT + B to select all surfaces on those brushes, and then apply the material.
The problem for me is that when I try to replace the materials and I write the name of the material I want to replace, the filter doesn’t find it, It happens randomly with many materials. but they are all in the same folder, so it doesn’t make any sense
Daniel,
If you haven’t already had your question answered, make sure that you create a material instance for the material you want to replace with.
I was having the same problem and this worked it out for me.
Finding this thread years later. Replying in case someone else, like me, is trying to figure this one out.
It looks like you can’t use the Delete Asset interface’s “Replace References” feature to replace a Material with a Material Instance. You can only select Materials. Likely it is the same in reverse; you can’t use it to replace a Material Instance with a Material.
I haven’t found a better method yet than manually replacing each Material with it’s correct Material Instance. It’s awful.
This can get really cumbersome, especially when replacing the Materials from Asset packs with a custom master material.
I wish we’d have a way around this.
Maybe with an utility widget? Im not versed in them, but Im trying somethings out…it could work…maybe. If I manage something Ill post it here
Guys, I think I found a good workaround to this problem thanks to chatGPT 
In short, use Property Matrix for bulk replacing the material with material instance.
Here are the steps in detail (I use UE 5.3.2):
That’s it! You can now delete the Material if you want.
I hope this works out for your case as well. Good luck!
I believe this method may only work if you are trying to replace in-level material references. In my case, I desired to change the material assignment at a project level.
Since this shows up in search engines…
From the content browser you replace references from material to material instance by chosing the material and material instance in question and select Asset Actions/Replace References from the contextual menu (right click).
You will get a warning that they are not the same class, but you can still replace references. Select the material instance (the one you want to keep) and click Consolidate. Unreal automatically deletes your original material after so you better have copied any textures from material to material instance before.
So for me, I have my main file in c4d… I brought everything to unreal and added materials… But everytime I go back to c4d and add a piece of geometry it screws up all my materials and gives me loads of different materials on the object. the most time consuming part is clicking ‘Display 21 materials’ and then 1 by 1 removing them so that I can reapply the correct material.
I was hoping I could just right click on ‘display 21 materials’ and click clear all or something 
