Shortly, maybe will add details later.
You can run git format-patch "branch_name_to_differentiate_commits". For example when you branch has 6 commits ahead of master, then this command will be like git format-patch master. It will generate 6 patch files. That command has other options to save files in directory which you like, etc.
Vise versa you can apply that changes by running git am "patch_file" and it will show up in commit history.
In my case it showed up some conflicts, but you can run git am -3 < "/path_patch", which makes some merge manipulations that ignore whitespaces, etc and show you only real conflicting cases, that could be solved with usual --continue, --abort.
More details: devconnected, stackoverflow.