Here’s the same Obsidian Canvas document open in Obsidian, and Hi-Canvas:

Image

Image

They’re not fully cross compatible, but as another user mentioned, the open source spec being worked on is picking up steam as the Open Canvas Working Group (OCWG) and even larger industry canvas platforms are trying to make the format something they can easily import and export in that open format.

So hopefully you won’t have to worry about migration much longer :)