Delete unnecessary lights, and resize the fog planes to reduce overlapping

After

The landscape is rather huge and unnecessary

Leave only visible parts

Delete parts of the environment in the behind

Make a function and name it

Get reference from Static Mesh Editor Subsystem and use Set Lods node to apply an preset lod array to the selected meshes

We then need to run the utility blueprint in the content browser

Time to make it work. Here's an unoptimized mesh with a decent amount of triangles

Right click in the content browser, the Set LODs function can be found under Scripted Asset Actions

With just a click, LODs are applied automatically

Set LODs for all our asset with ease!

LOD Coloration View

For meshes with the highest triangle count, set minimal LODs for them.

There's also potential for other functions using the asset action utility blueprint.

Use normal shsadow maps instead of virtual ones helps as well