Comment by rahimnathwani

Create an exfat partition called 'data' and mount it on both MacOS and Linux.

Then create your Documents, Downloads etc. folders on it, and use symbolic links.

e.g. on MacOS, do something like this for each 'shared' folder:

rm -rf /home/rahim/Downloads

mkdir /Volumes/data/Downloads

ln -s /Volumes/data/Downloads /home/rahim