On the mission of BepiColombo Mercury Magnetopheric Orbiter (MMO), we aim to investigate the properties of electromagnetic field and plasma wave phenomena at Mercury's magnetosphere and the interplanetary region around Mercury. For the subject we are developing software of EWO-OFA/WFC that is a component of PWI. The developing environment is placed at a laboratory of Kanazawa University, and the software is under developing. In our presentation, we will report the detail of the software and the status of development.