Sorry, this is beyond the scope of capacity of Multiwfn.
In order to calculate FCHT Resonance Raman, a matrix of 3*3*N of trans.dip moment derivatives is required as input (N=number of atoms) i.e for each of the 3 components of the trans.dip., 3 derivatives are required with respect to nuclear cart. coords for each atom. Can Multiwfn calculate this arrays between states? If not could it be implemented in a future version?