Annoying FPS eating (Cannot develop the game)

Hi, i bought these stuff: Archmodels for UE Vol ; Photorealistic Landscapes Bundle 1, thinking it will spare me big time. They do, however the rendering for them is terrible and i have a decent PC! :

intel i7-5820k 3.30GHz
64 GB RAM
EVGA GeForce GTX 980 Ti SC GAMING ACX 2.0+ 6GB DDR5 384-bit
ASRock X99 Extreme6/3.1
SSD HyperX FURY 240GB SATA-III 2.5 inch
-Running with Epic settings, duh-

Do i also have to pay someone to tell/show me how to optimize them? ‘‘Try disabling shadows’’, are you kidding me? I spent 500 eur to then disable my shadows in my 2 h game? It’s not even open world, just some foliage here and there.

Disabled DBugger Decals, i can see a difference in MaxShaderCom… view but the rendering is still bad.

Why does a grass/tree patch and 3 bushes take 80 FPS? Do i really need to have a grass patch in a radius of 20 m?

‘‘There is no specific answer for this, can you please check there: MaxShaderComplexityCount (checked, its disastrous), Directional Light Cascade Count (<4 and i can’t even see my character’s shadow)’’… and all this stuff and no actual solution to the problem, just pre-resolved answer from the Epic staff, like ‘‘yo check that out -link-’’ and it is ‘‘resolved’’. Is someone capable and with enough medals and awards to come up with an explanation?

I started working with Unreal Editor 1 year ago, since then I’ve studied the engine as i was developing my game. So this lag was not present in the 4.10 version, from which i constantly upgraded the project to newer versions.

Can anyone make this question the last one regarding this topic.
Can anyone share the almighty secret?

With regards,
Alex

You should provide in-depth details about the scene. Your question does not have any basic info to receive proper assistance.

updated

Directional Light

Without any further investigation I can safely say that you are getting expected performance as to your settings.
6 shadow cascades, covering 60000 units, coupled with relatively high-poly foliage with no LODs, that was designed primary for ArchViz. You are trying to render above 100 million triangles each frame. That is an order of magnitude above of what you should realistically aim for.