Overrides.toml for Scratch.jl?

[ThomasBreuer]

It is possible to share artifacts between several users by using a file Overrides.toml in the artifacts directory.
Is this functionality reasonable also for scratch spaces?
I am thinking of a big collection of files such that each file gets downloaded at runtime as soon as it is needed, and afterwards gets stored locally. The same cache could be accessed by several users.
(Of course one should then not use the feature that a package's scratch spaces are deleted as soon as the package is not used anymore.)