Thank you very Christian Hogrefe for all these details.
I expected challenges as those listed (from 1 to 4) and I am aware about the issue on mapping the different chemical species from a model to another.
I also thank you for your tips on sea salt and aerosols bins in EAC4 since I did not know about these issues.
I wonder if there is a working version of your tools where I can contribute (if I am able to do it). I am interested to explore the possibility to use CAMS as BCs and ICs for CMAQ, but if possible, I‘d rather avoid starting from scratch.
Saying this, I also thank Barron H. Henderson for his link. However, I am not fully sure to understand how I can adapt the codes for another model.
Matthieu