Hi! I’m thinking of trying FreedomBox! 
Will it run on my Odroid HC1?
Will running it locally only (so no port forwarding enabled) work?
Thank you!
Welcome!
Yes, you can. There is no pre-built image for that device, but this is not required. You will need to follow the installation guide.
Given you have both an SD card and an mmc drive on that machine you may want to consider:
- install to mmc drive and don’t use sd card (I would do this), or
- install /boot on sd ard and / filesystem on the mmc drive.
Have a go at it! I have been depending on FreedomBox for years now and am quite happy with it.