Hey there @ilozen! Creating different scripts and plugins for the editor is insanely powerful and can really streamline your pipeline! That said the subject is incredibly deep, so most of the resources I have on hand are quite dense! I have 2 learning sessions that show how the system works and goes over how to create the editor windows as well as the functionality behind them! Don’t be off-put by their length, they were originally streams but insanely useful information nonetheless!
Here Tom Shannon use BPs to create a little editor tool to change LODs for a bunch of objects at once, then a couple minutes later shows you how to actually make the UI portion and buttons. (Timestamped it where he starts actually making the tool but feel free to watch the whole thing)
Now if you’re more of the C++ side of things, there’s another training:
That one’s a bit more advanced but insanely useful for extending the engine. Hope this helps!