
Being manual lenses the case, you can use both. If you plan to use EF manual lenses I think is better to go with the EF mount version.
If you want the best out of manual lenses, I would go with MFT mount and get the Speedbooster, with Nikon mount lenses.
I explain: for example, the Zeiss ZF are all manual and will work on both cameras with an adapter, but there's a plus for the MFT mount if you add the Speedbooster in-between.
You loose less field of view, you gain one F stop, and gain resolution in the transfer modulation.
You cannot use the SpeedB with EF mount.
So, manual lenses work in both, it all depends on the lenses you wish to use, and there's a plus on MFT version when using Speedbooster and Nikon mount. And the glass made for MFT is closer to what the sensor size requires... If you invested on EF glass already then I would say go with EF mount. If not, even without the SpeedB you can get SLR magic or Voightlangers wich are manual, and great, and design for this type of sensor.
Hope this helps.