I know that this seems pretty old, however I just did a rebuild on my machine, and put an ssd in for the system drive. I wanted to move as much off of that drive as possible, and ran across this while trying to move some files.
the global editor preferences derivedDataCache ->advanced → local section
set to->: %GAMEDIR%LocalDerivedDataCache
was the best place to move each cache to the current project path. No Files to Edit, and the best part is that it seems to propogate to all my other projects running on the same version. So I only have needed to change it once for each engine version.