Call Riemannian metric from matlab stan

[nikfio]

Hi everyone,
I am using matlabstan, in particular the mcmc sampling method with hamiltonian or nuts.
I noticed in stan code there is an implementation of metrics not specified in matlabstan, like Riemannian manifold with SoftAbs metric, Euclidean manifold with dense metric and so on...
How is it possible to call these engine solvers?
In my opinion it is a thing of correctly using matlabstan process manager to specify right command to cmdstan, but actually I don't know how to exactly do the all process.
Does someone have an idea about?

Thanks