The easier way to get mc in recalbox is "steal" it to a raspbian we previously installed it.
These are the files and folders you need to copy:
You can copy the files by ssh, using the same mc if you have GNU/Linux in your PC (plug the cart to the PC), from raspbian if you have this system and recalbox, WinSCP if you use Windows, etc...
If you haven't raspbian here you are all the necesary files, each in the correct path.
Warning: you probably need copy again each time Recalbox will be updated (This is a fast and simple operation and Recalbox is updated every long time).
Anyway, if you want mc will be part of recalbox you can join to the request I asked in the official forum.