No idea about zfs support on macOS, that would be cool.
I have this stack exchange thread bookmarked and ive always been able to mount HFS+ drives on Linux using it.[1] Not the most stable thing in the world but generally fine as long as you're careful about mounting/unmounting properly.
Besides that exfat is probably the way to go. I know it isn't ideal but it works.
[1] https://askubuntu.com/questions/332315/how-to-read-and-write...