Not really a fan of ^THIS^ fwiw… It may work, but it has a nasty side-affect. In many versions of the editor, it forces an immediate full-shader re-compile without warning, which can be a lengthy PITA process which prevents you from doing any real work in the meantime (especially if you switch over, then try another, and then back again). Same with switching between DX12 vs DX11 iirc. A 1080Ti with DX12? Its going to cook itself, if it can even manage it. 
Also, when you’re starting out you often have lots of 3rd-Party marketplace packs all in one project as a jumping off point (easily hundreds when you include all the freebies). These are usually all separate assets with their own unique meshes and materials. And there are some really heavy assets in there too like all the Megascans stuff. And you’re opening up and closing things rapidly looking for the right assets to get started with. Slow workflow. 
Lowering the quality also gives you no reference point about where the scene is at. So its better to just CAP the frame rate instead imho (t.maxfps or whatever in the console window) and stay on Epic settings for as long as possible in the beginning at least. So you have a better idea of where the scene is at, or just work with Realtime OFF in most of the Editors.
^This^… As was hinted already… Stay well way from vegetation especially Megascans at the start anyway, unless you just have to have photo-realistic cinematic scenes with lush forests.
Example: