The documentation of the Julia wapper to the Clp solver is a bit out of date. Under options, “SolveType” is still listed but it looks like it has been replaced by “Algorithm”: https://github.com/jump-dev/Clp.jl
Options for scaling are not documented in the Julia wrapper. I managed to find some documentation on the options for scaling here: Clp: ClpModel Class Reference
Sets or unsets scaling, 0 -off, 1 equilibrium, 2 geometric, 3 auto, 4 auto-but-as-initialSolve-in-bab
The code below works for me:
model = Model(Clp.Optimizer)
set_optimizer_attribute(model,"Scaling",1)
It may be worth updating the documentation.