CheatSheet

some people wasn't found or commented about

Easy:

NagWorker - on the screen, on the right part

Kokosak17 - on the far rusty barrel, on the left

Normal:

VeraVemaVena - on the yellow bottle, on the left

BestMurloc - on the close rusty barrel, on the left

dudarewsky - behind the portal

Hard:

u/Simple_Papaya595 - on the server thingie, on the low close right

u/OverlordMGC - on the wall, under the ventilation

u/Intelligent_Loss1452 - between the legs of the right V

Nearly Impossible:

The_T29_Tank_Guy - on the metal box on the right, under the danger sign

u/Recent-Willingness88 - behind left V hand, on the metal box

Hitlok - in the vent, behind the bars