You should be fine with a strymon ojai. Each port puts out 9V DC at 500mA. I power my MFC with 9V DC just fine.
From:
https://forum.fractalaudio.com/threads/wireless-midi.29044/#post-427142
FractalAudio said: "The MFC can actually be run on DC (the supply section is a switching converter). Power consumption is actually pretty good. With all LEDs on the consumption should be less than 500 mA."
Just keep in mind that the MFC power jack has AC dimension pin:
From:
https://forum.fractalaudio.com/thre...axe-what-connection-it-is.86760/#post-1049803
FractalAudio said: "2.1mm is the standard for DC. 2.5mm is the standard for AC."
You might need a custom cable with a 2.1mm on the Strymon Ojai end and a 2.5mm on the MFC end. The DC voltage would be fine though.