The simulation of CVS-EOM L-edge spectra is enabled in Q-Chem 5.4 using a two-step state interaction approach, as described in the following article:
https://doi.org/10.1021/acs.jpclett.0c02027
In the first step, one needs to compute the target CVS-EOM states and corresponding SOCs using Q-Chem.
From the Q-Chem output, one can construct the SO Hamiltonian, which needs to be diagonalized to correct the energies and oscillator strengths.
This can be done using the l-edge program available in the following git repository:
https://gitlab.com/malop/l-edge
Instructions and examples on how to run it and on how to set up the corresponding Q-Chem inputs can also be found there.