MicroMV (.mmv) files are special multimedia files saved in a videotape format introduced in 2001 by Sony. The support for this file format is pretty low nowadays, but perhaps Nero Multimedia Suite (at least in some of its versions) might still support MMV format and could convert it to other multimedia formats, including Apple Quicktime MOV format. But overall options for mmv to mov conversion (export to QuickTime movie) are pretty much limited.
Open MMV file Open MOV file