Will it be feasible (and hopefully trivial) to install pymavlink onto the OpenMV board?
It looks like there’s a lot of PC side software for that program. What part of it do you want explicitly? Just the serial code?
You should be able to use files like this part of it without much modification: pymavlink/fgFDM.py at master · ArduPilot/pymavlink · GitHub
Just install all the parts of the program you want on your SD card and then import the files directly into your script. If they compile find then should work. Otherwise, fix whatever compile errors appear and keep working.