I still have them in my library, plus some additional ones.
I have a Release and Preview version of the engine from source installed.
In my launcher library there are two of each of these engine projects.
AutoRTFMTests
ChaosVisualDebugger
SlateUGS
SubmitTool
UnrealLightmass
Unsync
I also have a launcher version of the engine but there isn’t a third copy of the projects, so I think they only happen when compiling from source files.
I looked how to get rid of them but never found an answer, so I just ignore them.