There is only one file type that uses the .MOEF extension:
Apple Motion Effect Project Template
A MOEF file is an effect project template created by Apple Motion, a motion graphics application for macOS. It contains project information about an effect, which includes filters and behaviors applied to the effect. MOEF files do not contain the actual media that makes up the effect only references to the media.
Apple Motion uses several extensions for saving different project types. Titles created in Motion are saved as .MOTI files, generators are saved as .MOTN files, and transitions are saved as .MOTR files.
By default, MOEF files are saved in the following directory in macOS:
MOEF files are commonly found in the "Effects" folder accompanied by two .PNG thumbnail previews, a .MOV preview of the MOEF effect, and a media folder that stores all the media associated with the project.
Apple Motion is used for creating effects, transitions, titles, and generators for video projects. It is designed to be a companion program to a video editor for creating an effect, title, transition, which is then imported into the video editor. Motion is most commonly used with Final Cut Pro because of its similar appearance and integration with the video editor.
Updated: September 29, 2017