Thanks for reported, you can override following language constant translation in your backend language override section.

COM_EASYBLOG_TOOLBAR_CALENDAR="日曆"

COM_EASYBLOG_CALENDAR_LOADING_CALENDAR="請稍候，我們正在呈現日曆中"

COM_EASYBLOG_SH404_ROUTER_CALENDAR="日曆"

COM_EASYBLOG_SH404_VIEW_CALENDAR="日曆"

You can refer this documentation here : https://stackideas.com/docs/easyblog/administrators/how-tos/how-to-create-language-string-override

Hope this will help.