The ability to create custom filters in Unreal Engine 5 is a great quality of life improvement inside the editor. It is not only useful to filter out Assets in Content Browser but also can be used in the Outliner to filter out Actors while working on level design, look-dev, etc.
https://dev.epicgames.com/community/learning/tutorials/jMj2/unreal-engine-creating-custom-filters-in-ue5
Is it possible to create a filter for texture dimensions?
Yes, you can filter with texture dimensions. To do that, try using “Dimensions=2048” as an example. Make sure to use the word Dimensions with ‘s’ and for the value I noticed that it takes only one axis value. Hope this will help.